Appendix I
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Albania | 1998 | 2007 | 2 | 1 | 0.677 | 9 |
| Albania | 1998 | 2008 | 2 | 0.677 | 9 | |
| Albania | 1998 | 2012 | 1 | 0.677 | 9 | |
| Argentina | 1983 | 1994 | 3 | 2 | 1.277 | 7 |
| Argentina | 1983 | 1997 | 1 | 1.277 | 7 | |
| Armenia | 1995 | 2005 | In house | 3 | 0.677 | 5 |
| Australia | 1901 | 1907 | 1 | 1 | 1.093 | 10 |
| Australia | 1901 | 1910 | 1 | 1.093 | 10 | |
| Australia | 1901 | 1929 | 1 | 1.093 | 10 | |
| Australia | 1901 | 1942 | 3 | 1.093 | 10 | |
| Australia | 1901 | 1946 | 3 | 1.093 | 10 | |
| Australia | 1901 | 1967 | 1 | 1.093 | 10 | |
| Australia | 1901 | 1977 | 1 | 1.093 | 10 | |
| Australia | 1901 | 1985 | 1 | 1.093 | 10 | |
| Austria | 1945 | 1946 | 2 | 1 | 0.667 | 10 |
| Austria | 1945 | 1948 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1954 | No amendment | 0.667 | 10 | |
| Austria | 1945 | 1955 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1956 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1958 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1959 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1960 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1961 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1962 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1963 | 1 | 0.667 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Austria | 1945 | 1964 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1968 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1969 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1972 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1973 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1974 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1975 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1977 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1979 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1981 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1982 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1983 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1984 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1986 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1987 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1988 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1990 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1991 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1992 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1993 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1994 | 3 | 0.667 | 10 | |
| Austria | 1945 | 1996 | 2 | 0.667 | 10 | |
| Austria | 1945 | 1997 | 1 | 0.667 | 10 | |
| Austria | 1945 | 1998 | 1 | 0.667 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Austria | 1945 | 1999 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2000 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2001 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2002 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2003 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2004 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2005 | 2 | 0.667 | 10 | |
| Austria | 1945 | 2007 | 2 | 0.667 | 10 | |
| Austria | 1945 | 2008 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2009 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2010 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2011 | 1 | 0.667 | 10 | |
| Austria | 1945 | 2012 | 2 | 0.667 | 10 | |
| Austria | 1945 | 2013 | 1 | 0.667 | 10 | |
| Belgium | 1831 | 1893 | In house | 3 | 0.707 | 6 |
| Belgium | 1831 | 1920 | 2 | 0.707 | 9 | |
| Belgium | 1831 | 1921 | 3 | 0.707 | 9 | |
| Belgium | 1831 | 1968 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1969 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1970 | 3 | 0.707 | 10 | |
| Belgium | 1831 | 1971 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1980 | 2 | 0.707 | 10 | |
| Belgium | 1831 | 1981 | 2 | 0.707 | 10 | |
| Belgium | 1831 | 1983 | 2 | 0.707 | 10 | |
| Belgium | 1831 | 1984 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1985 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1988 | 2 | 0.707 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Belgium | 1831 | 1989 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1991 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1993 | 3 | 0.707 | 10 | |
| Belgium | 1831 | 1994 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1996 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1997 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1998 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 1999 | 2 | 0.707 | 10 | |
| Belgium | 1831 | 2000 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 2001 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 2002 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 2003 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 2004 | 1 | 0.707 | 10 | |
| Belgium | 1831 | 2005 | 2 | 0.707 | 10 | |
| Belgium | 1831 | 2007 | 1 | 0.707 | 8 | |
| Belgium | 1831 | 2008 | 1 | 0.707 | 8 | |
| Belgium | 1831 | 2012 | 1 | 0.707 | 8 | |
| Botswana | 1966 | 1969 | In house | 2 | 0.667 | 6 |
| Botswana | 1966 | 1970 | 2 | 0.667 | 6 | |
| Botswana | 1966 | 1972 | 1 | 0.667 | 6 | |
| Botswana | 1966 | 1973 | 2 | 0.667 | 6 | |
| Botswana | 1966 | 1978 | 1 | 0.667 | 6 | |
| Botswana | 1966 | 1982 | 2 | 0.667 | 6 | |
| Botswana | 1966 | 1983 | 1 | 0.667 | 6 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Botswana | 1966 | 1987 | 2 | 0.667 | 7 | |
| Botswana | 1966 | 1992 | 1 | 0.667 | 7 | |
| Botswana | 1966 | 1993 | 1 | 0.667 | 7 | |
| Botswana | 1966 | 1997 | 3 | 0.667 | 8 | |
| Botswana | 1966 | 1999 | 2 | 0.667 | 8 | |
| Botswana | 1966 | 2002 | 2 | 0.667 | 8 | |
| Botswana | 1966 | 2005 | 2 | 0.667 | 8 | |
| Brazil | 1988 | 1992 | 1 | 2 | 0.702 | 8 |
| Brazil | 1988 | 1993 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 1994 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 1995 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 1996 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 1997 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 1998 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 1999 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 2000 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2001 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 2002 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2003 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2004 | 2 | 0.702 | 8 | |
| Brazil | 1988 | 2005 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2006 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2007 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2008 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2009 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2010 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2011 | 1 | 0.702 | 8 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Brazil | 1988 | 2012 | 1 | 0.702 | 8 | |
| Brazil | 1988 | 2013 | 2 | 0.702 | 8 | |
| Bulgaria | 1991 | 2003 | 2 | 1 | 0.77 | 9 |
| Bulgaria | 1991 | 2005 | 1 | 0.77 | 9 | |
| Bulgaria | 1991 | 2006 | 3 | 0.77 | 9 | |
| Bulgaria | 1991 | 2007 | 2 | 0.77 | 9 | |
| Canada | 1867 | 1893 | 1 | 1 | 1.167 | 9 |
| Canada | 1867 | 1907 | 1 | 1.167 | 9 | |
| Canada | 1867 | 1915 | 2 | 1.167 | 9 | |
| Canada | 1867 | 1916 | 1 | 1.167 | 9 | |
| Canada | 1867 | 1927 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1930 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1940 | 2 | 1.167 | 10 | |
| Canada | 1867 | 1943 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1946 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1949 | 2 | 1.167 | 10 | |
| Canada | 1867 | 1951 | 2 | 1.167 | 10 | |
| Canada | 1867 | 1952 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1960 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1964 | 2 | 1.167 | 10 | |
| Canada | 1867 | 1965 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1974 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1975 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1982 | 3 | 1.167 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Canada | 1867 | 1983 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1986 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1987 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1992 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1993 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1997 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1998 | 1 | 1.167 | 10 | |
| Canada | 1867 | 1999 | 2 | 1.167 | 10 | |
| Canada | 1867 | 2001 | 1 | 1.167 | 10 | |
| Canada | 1867 | 2011 | 1 | 1.167 | 10 | |
| Cape Verde | 1992 | 1992 | 1 | No amendment | 0.667 | 8 |
| Cape Verde | 1992 | 1995 | 1 | 0.667 | 8 | |
| Cape Verde | 1992 | 1999 | 2 | 0.667 | 8 | |
| Cape Verde | 1992 | 2010 | 2 | 0.667 | 10 | |
| Chile | 1980 | 1989 | 1 | 2 | 1.19 | 8 |
| Chile | 1980 | 1991 | 2 | 1.19 | 8 | |
| Chile | 1980 | 1994 | 2 | 1.19 | 8 | |
| Chile | 1980 | 1996 | 1 | 1.19 | 8 | |
| Chile | 1980 | 1997 | 2 | 1.19 | 8 | |
| Chile | 1980 | 1998 | 1 | 1.19 | 8 | |
| Chile | 1980 | 1999 | 1 | 1.19 | 8 | |
| Chile | 1980 | 2000 | 1 | 1.19 | 9 | |
| Chile | 1980 | 2001 | 1 | 1.19 | 9 | |
| Chile | 1980 | 2003 | 1 | 1.19 | 9 | |
| Chile | 1980 | 2005 | 3 | 1.19 | 9 | |
| Chile | 1980 | 2007 | 1 | 1.19 | 10 | |
| Chile | 1980 | 2008 | 1 | 1.19 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Chile | 1980 | 2009 | 2 | 1.19 | 10 | |
| Chile | 1980 | 2011 | 1 | 1.19 | 10 | |
| Chile | 1980 | 2012 | 1 | 1.19 | 10 | |
| Chile | 1980 | 2013 | 1 | 1.19 | 10 | |
| Colombia | 1991 | 1993 | 5 | 1 | 0.536 | 9 |
| Colombia | 1991 | 1995 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 1996 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 1997 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 1999 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 2000 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 2001 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 2002 | 2 | 0.536 | 7 | |
| Colombia | 1991 | 2003 | 3 | 0.536 | 7 | |
| Colombia | 1991 | 2004 | 2 | 0.536 | 7 | |
| Colombia | 1991 | 2005 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 2007 | 1 | 0.536 | 7 | |
| Colombia | 1991 | 2009 | 2 | 0.536 | 7 | |
| Colombia | 1991 | 2011 | 3 | 0.536 | 7 | |
| Colombia | 1991 | 2012 | 2 | 0.536 | 7 | |
| Colombia | 1991 | 2013 | 1 | 0.536 | 7 | |
| Comoros | 2001 | 2009 | In house | 3 | 1.333 | 9 |
| Costa Rica | 1949 | 1954 | 1 | 2 | 1.187 | 10 |
| Costa Rica | 1949 | 1956 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1957 | 3 | 1.187 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Costa Rica | 1949 | 1958 | 1 | 1.187 | 10 | |
| Costa Rica | 1949 | 1959 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1961 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1963 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1965 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1968 | 3 | 1.187 | 10 | |
| Costa Rica | 1949 | 1969 | 3 | 1.187 | 10 | |
| Costa Rica | 1949 | 1971 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1972 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1973 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1975 | 3 | 1.187 | 10 | |
| Costa Rica | 1949 | 1977 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1981 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1982 | 1 | 1.187 | 10 | |
| Costa Rica | 1949 | 1984 | 1 | 1.187 | 10 | |
| Costa Rica | 1949 | 1987 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1989 | 3 | 1.187 | 10 | |
| Costa Rica | 1949 | 1991 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1993 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1994 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1995 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1996 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1997 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 1999 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 2000 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 2001 | 1 | 1.187 | 10 | |
| Costa Rica | 1949 | 2002 | 3 | 1.187 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Costa Rica | 1949 | 2003 | 2 | 1.187 | 10 | |
| Costa Rica | 1949 | 2011 | 2 | 1.187 | 10 | |
| Croatia | 1991 | 2000 | In house | 2 | 0.697 | 8 |
| Croatia | 1991 | 2001 | 2 | 0.697 | 8 | |
| Croatia | 1991 | 2010 | 1 | 0.697 | 9 | |
| Cyprus | 1960 | 1989 | 1 | 2 | 1.343 | 10 |
| Cyprus | 1960 | 1996 | 2 | 1.343 | 10 | |
| Cyprus | 1960 | 2002 | 2 | 1.343 | 10 | |
| Cyprus | 1960 | 2006 | 3 | 1.343 | 10 | |
| Cyprus | 1960 | 2010 | 1 | 1.343 | 10 | |
| Cyprus | 1960 | 2013 | 1 | 1.343 | 10 | |
| Czech Republic | 1993 | 1998 | In house | 1 | 0.887 | 10 |
| Czech Republic | 1993 | 2000 | 1 | 0.887 | 10 | |
| Czech Republic | 1993 | 2001 | 1 | 0.887 | 10 | |
| Czech Republic | 1993 | 2002 | 3 | 0.887 | 10 | |
| Czech Republic | 1993 | 2009 | 1 | 0.887 | 9 | |
| Czech Republic | 1993 | 2012 | 2 | 0.887 | 9 | |
| Czech Republic | 1993 | 2013 | No amendment | 0.887 | 9 | |
| Ecuador | 2011 | In house | 2 | 1.18 | 5 | |
| El Salvador | 1983 | 1991 | 1 | 1 | 0.677 | 7 |
| El Salvador | 1983 | 1992 | 1 | 0.677 | 7 | |
| El Salvador | 1983 | 1993 | 1 | 0.677 | 7 | |
| El Salvador | 1983 | 1994 | 1 | 0.677 | 7 | |
| El Salvador | 1983 | 1996 | 1 | 0.677 | 7 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| El Salvador | 1983 | 1999 | 1 | 0.677 | 7 | |
| El Salvador | 1983 | 2000 | 2 | 0.677 | 7 | |
| El Salvador | 1983 | 2003 | No amendment | 0.677 | 7 | |
| El Salvador | 1983 | 2009 | 1 | 0.677 | 8 | |
| Estonia | 1992 | 2003 | In house | 3 | 1.11 | 9 |
| Estonia | 1992 | 2007 | 1 | 1.11 | 9 | |
| Estonia | 1992 | 2011 | 1 | 1.11 | 9 | |
| Finland | 1999 | 2007 | 1 | 1 | 1.157 | 10 |
| Finland | 1999 | 2011 | 1 | 1.157 | 10 | |
| France | 1958 | 1960 | In house | 2 | 1.086 | 5 |
| France | 1958 | 1962 | 3 | 1.086 | 5 | |
| France | 1958 | 1963 | 1 | 1.086 | 5 | |
| France | 1958 | 1974 | 2 | 1.086 | 8 | |
| France | 1958 | 1976 | 1 | 1.086 | 8 | |
| France | 1958 | 1992 | 2 | 1.086 | 9 | |
| France | 1958 | 1993 | 1 | 1.086 | 9 | |
| France | 1958 | 1995 | 1 | 1.086 | 9 | |
| France | 1958 | 1996 | 1 | 1.086 | 9 | |
| France | 1958 | 1998 | 1 | 1.086 | 9 | |
| France | 1958 | 1999 | 2 | 1.086 | 9 | |
| France | 1958 | 2000 | 1 | 1.086 | 9 | |
| France | 1958 | 2003 | 1 | 1.086 | 9 | |
| France | 1958 | 2005 | 1 | 1.086 | 9 | |
| France | 1958 | 2008 | 2 | 1.086 | 9 | |
| Georgia | 1995 | 2000 | In house | 2 | 0.697 | 5 |
| Georgia | 1995 | 2001 | 3 | 0.697 | 5 | |
| Georgia | 1995 | 2002 | 1 | 0.697 | 5 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Georgia | 1995 | 2003 | 2 | 0.697 | 5 | |
| Georgia | 1995 | 2004 | 1 | 3 | 0.697 | 7 |
| Georgia | 1995 | 2005 | 2 | 0.697 | 7 | |
| Georgia | 1995 | 2006 | 1 | 0.697 | 7 | |
| Georgia | 1995 | 2008 | 2 | 0.697 | 6 | |
| Georgia | 1995 | 2009 | 3 | 0.697 | 6 | |
| Georgia | 1995 | 2010 | 3 | 0.697 | 6 | |
| Georgia | 1995 | 2011 | 2 | 0.697 | 6 | |
| Georgia | 1995 | 2012 | 1 | 0.697 | 6 | |
| Georgia | 1995 | 2013 | 2 | 0.697 | 7 | |
| Germany | 1949 | 1951 | 1 | 1 | 0.864 | 10 |
| Germany | 1949 | 1952 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1953 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1954 | 2 | 0.864 | 10 | |
| Germany | 1949 | 1955 | 2 | 0.864 | 10 | |
| Germany | 1949 | 1956 | 2 | 0.864 | 10 | |
| Germany | 1949 | 1957 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1959 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1961 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1965 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1967 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1968 | 2 | 0.864 | 10 | |
| Germany | 1949 | 1969 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1970 | 1 | 0.864 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Germany | 1949 | 1971 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1972 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1975 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1976 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1983 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1990 | 3 | 0.864 | 10 | |
| Germany | 1949 | 1992 | 2 | 0.864 | 10 | |
| Germany | 1949 | 1993 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1994 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1995 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1997 | 1 | 0.864 | 10 | |
| Germany | 1949 | 1998 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2000 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2001 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2002 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2006 | 2 | 0.864 | 10 | |
| Germany | 1949 | 2008 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2009 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2010 | 1 | 0.864 | 10 | |
| Germany | 1949 | 2012 | 1 | 0.864 | 10 | |
| Greece | 1975 | 1986 | 1 | 2 | 1.1 | 10 |
| Greece | 1975 | 2001 | 1 | 1.1 | 10 | |
| Greece | 1975 | 2008 | 1 | 1.1 | 10 | |
| Guyana | 1980 | 1992 | In house | 2 | 1 | 6 |
| Guyana | 1980 | 1995 | 2 | 1 | 6 | |
| Guyana | 1980 | 2000 | 2 | 1 | 6 | |
| Guyana | 1980 | 2001 | 2 | 1 | 6 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Guyana | 1980 | 2003 | 3 | 1 | 6 | |
| Guyana | 1980 | 2007 | 1 | 1 | 6 | |
| Honduras | 1982 | 1984 | In house | 1 | 0.687 | 6 |
| Honduras | 1982 | 1986 | 2 | 0.687 | 5 | |
| Honduras | 1982 | 1987 | 1 | 0.687 | 5 | |
| Honduras | 1982 | 1988 | 1 | 0.687 | 5 | |
| Honduras | 1982 | 1990 | 1 | 0.687 | 6 | |
| Honduras | 1982 | 1991 | 1 | 0.687 | 6 | |
| Honduras | 1982 | 1995 | 1 | 0.687 | 6 | |
| Honduras | 1982 | 1996 | 1 | 0.687 | 6 | |
| Honduras | 1982 | 1998 | 1 | 0.687 | 6 | |
| Honduras | 1982 | 1999 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2000 | 2 | 0.687 | 7 | |
| Honduras | 1982 | 2001 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2002 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2003 | 2 | 0.687 | 7 | |
| Honduras | 1982 | 2004 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2005 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2008 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2011 | 1 | 0.687 | 7 | |
| Honduras | 1982 | 2012 | No amendment | 0.687 | 7 | |
| Honduras | 1982 | 2013 | No amendment | 0.687 | 7 | |
| Hungary | 2011 | 2012 | 2 | 3 | 0.677 | 10 |
| Hungary | 2011 | 2013 | 3 | 0.677 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Iceland | 1944 | 1959 | 1 | 1 | 1.01 | 10 |
| Iceland | 1944 | 1968 | 2 | 1.01 | 10 | |
| Iceland | 1944 | 1984 | 2 | 1.01 | 10 | |
| Iceland | 1944 | 1991 | 2 | 1.01 | 10 | |
| Iceland | 1944 | 1995 | 2 | 1.01 | 10 | |
| Iceland | 1944 | 1999 | 1 | 1.01 | 10 | |
| Iceland | 1944 | 2013 | 3 | 1.01 | 10 | |
| India | 1949 | 1951 | In house | 3 | 0.56 | 9 |
| India | 1949 | 1952 | 1 | 0.56 | 9 | |
| India | 1949 | 1954 | 1 | 0.56 | 9 | |
| India | 1949 | 1955 | 2 | 0.56 | 9 | |
| India | 1949 | 1956 | 3 | 0.56 | 9 | |
| India | 1949 | 1959 | 2 | 0.56 | 9 | |
| India | 1949 | 1960 | 1 | 0.56 | 9 | |
| India | 1949 | 1961 | 2 | 0.56 | 9 | |
| India | 1949 | 1962 | 2 | 0.56 | 9 | |
| India | 1949 | 1963 | 2 | 0.56 | 9 | |
| India | 1949 | 1964 | 2 | 0.56 | 9 | |
| India | 1949 | 1966 | 1 | 0.56 | 9 | |
| India | 1949 | 1967 | 1 | 0.56 | 9 | |
| India | 1949 | 1969 | 3 | 0.56 | 9 | |
| India | 1949 | 1971 | 2 | 0.56 | 9 | |
| India | 1949 | 1972 | 3 | 0.56 | 9 | |
| India | 1949 | 1973 | 2 | 0.56 | 9 | |
| India | 1949 | 1974 | 1 | 0.56 | 9 | |
| India | 1949 | 1975 | 3 | 0.56 | 7 | |
| India | 1949 | 1976 | 3 | 0.56 | 7 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| India | 1949 | 1977 | 3 | 0.56 | 8 | |
| India | 1949 | 1978 | 3 | 0.56 | 8 | |
| India | 1949 | 1980 | 2 | 0.56 | 8 | |
| India | 1949 | 1982 | 2 | 0.56 | 8 | |
| India | 1949 | 1984 | 2 | 0.56 | 8 | |
| India | 1949 | 1985 | 3 | 0.56 | 8 | |
| India | 1949 | 1986 | 1 | 0.56 | 8 | |
| India | 1949 | 1987 | 2 | 0.56 | 8 | |
| India | 1949 | 1988 | 2 | 0.56 | 8 | |
| India | 1949 | 1989 | 2 | 0.56 | 8 | |
| India | 1949 | 1990 | 2 | 0.56 | 8 | |
| India | 1949 | 1991 | 2 | 0.56 | 8 | |
| India | 1949 | 1992 | 2 | 0.56 | 8 | |
| India | 1949 | 1993 | 1 | 0.56 | 8 | |
| India | 1949 | 1994 | 2 | 0.56 | 8 | |
| India | 1949 | 1995 | 2 | 0.56 | 9 | |
| India | 1949 | 1999 | 2 | 0.56 | 9 | |
| India | 1949 | 2000 | 2 | 0.56 | 9 | |
| India | 1949 | 2001 | 1 | 0.56 | 9 | |
| India | 1949 | 2002 | 2 | 0.56 | 9 | |
| India | 1949 | 2003 | 2 | 0.56 | 9 | |
| India | 1949 | 2005 | 2 | 0.56 | 9 | |
| India | 1949 | 2006 | 1 | 0.56 | 9 | |
| India | 1949 | 2009 | 2 | 0.56 | 9 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| India | 1949 | 2011 | 1 | 0.56 | 9 | |
| India | 1949 | 2012 | 1 | 0.56 | 9 | |
| Indonesia | 1959 | 1999 | 1 | 2 | 0.51 | 6 |
| Indonesia | 1959 | 2000 | 3 | 0.51 | 6 | |
| Indonesia | 1959 | 2001 | 3 | 0.51 | 6 | |
| Indonesia | 1959 | 2002 | 3 | 0.51 | 6 | |
| Ireland | 1937 | 1939 | 2 | 1 | 1.085 | 8 |
| Ireland | 1937 | 1941 | 1 | 1.085 | 8 | |
| Ireland | 1937 | 1972 | 3 | 1.085 | 10 | |
| Ireland | 1937 | 1973 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 1979 | 1 | 1.085 | 10 | |
| Ireland | 1937 | 1983 | 3 | 1.085 | 10 | |
| Ireland | 1937 | 1984 | 1 | 1.085 | 10 | |
| Ireland | 1937 | 1987 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 1992 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 1996 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 1997 | 1 | 1.085 | 10 | |
| Ireland | 1937 | 1998 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 1999 | 3 | 1.085 | 10 | |
| Ireland | 1937 | 2001 | 1 | 1.085 | 10 | |
| Ireland | 1937 | 2002 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 2004 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 2009 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 2011 | 1 | 1.085 | 10 | |
| Ireland | 1937 | 2012 | 2 | 1.085 | 10 | |
| Ireland | 1937 | 2013 | 1 | 1.085 | 10 | |
| Israel | 1958 | 1959 | In house | 1 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Israel | 1958 | 1960 | 1 | 0.5 | 10 | |
| Israel | 1958 | 1964 | 1 | 0.5 | 10 | |
| Israel | 1958 | 1967 | 1 | 0.5 | 9 | |
| Israel | 1958 | 1968 | 3 | 0.5 | 9 | |
| Israel | 1958 | 1969 | 1 | 0.5 | 9 | |
| Israel | 1958 | 1974 | 1 | 0.5 | 9 | |
| Israel | 1958 | 1975 | 2 | 0.5 | 9 | |
| Israel | 1958 | 1976 | 2 | 0.5 | 9 | |
| Israel | 1958 | 1980 | 2 | 0.5 | 9 | |
| Israel | 1958 | 1981 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1982 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1983 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1984 | 3 | 0.5 | 6 | |
| Israel | 1958 | 1985 | 2 | 0.5 | 6 | |
| Israel | 1958 | 1987 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1988 | 2 | 0.5 | 6 | |
| Israel | 1958 | 1991 | 2 | 0.5 | 6 | |
| Israel | 1958 | 1992 | 3 | 0.5 | 6 | |
| Israel | 1958 | 1994 | 2 | 0.5 | 6 | |
| Israel | 1958 | 1995 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1996 | 2 | 0.5 | 6 | |
| Israel | 1958 | 1997 | 1 | 0.5 | 6 | |
| Israel | 1958 | 1998 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2000 | 2 | 0.5 | 6 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Israel | 1958 | 2001 | 2 | 0.5 | 6 | |
| Israel | 1958 | 2002 | 2 | 0.5 | 6 | |
| Israel | 1958 | 2003 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2004 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2005 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2006 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2007 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2008 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2010 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2012 | 1 | 0.5 | 6 | |
| Israel | 1958 | 2013 | 1 | 0.5 | 6 | |
| Italy | 1947 | 1948 | 2 | 1 | 1.095 | 10 |
| Italy | 1947 | 1953 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1958 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1963 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1967 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1989 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1991 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1992 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1993 | 1 | 1.095 | 10 | |
| Italy | 1947 | 1999 | 1 | 1.095 | 10 | |
| Italy | 1947 | 2000 | 1 | 1.095 | 10 | |
| Italy | 1947 | 2001 | 2 | 1.095 | 10 | |
| Italy | 1947 | 2002 | 1 | 1.095 | 10 | |
| Italy | 1947 | 2003 | 1 | 1.095 | 10 | |
| Italy | 1947 | 2007 | 1 | 1.095 | 10 | |
| Italy | 1947 | 2012 | 1 | 1.095 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Jamaica | 1962 | 1971 | In house | 1 | 0.532 | 10 |
| Jamaica | 1962 | 1975 | 1 | 0.532 | 10 | |
| Jamaica | 1962 | 1977 | 1 | 0.532 | 10 | |
| Jamaica | 1962 | 1986 | 1 | 0.532 | 10 | |
| Jamaica | 1962 | 1990 | 1 | 0.532 | 10 | |
| Jamaica | 1962 | 1993 | 2 | 0.532 | 9 | |
| Jamaica | 1962 | 1994 | 2 | 0.532 | 9 | |
| Jamaica | 1962 | 1999 | 2 | 0.532 | 9 | |
| Jamaica | 1962 | 2002 | 2 | 0.532 | 9 | |
| Jamaica | 1962 | 2009 | 1 | 0.532 | 9 | |
| Jamaica | 1962 | 2011 | 3 | 0.532 | 9 | |
| Latvia | 1991 | 1994 | In house | 2 | 0.687 | 8 |
| Latvia | 1991 | 1996 | 2 | 0.687 | 8 | |
| Latvia | 1991 | 1997 | 3 | 0.687 | 8 | |
| Latvia | 1991 | 1998 | 2 | 0.687 | 8 | |
| Latvia | 1991 | 2002 | 1 | 0.687 | 8 | |
| Latvia | 1991 | 2003 | 3 | 0.687 | 8 | |
| Latvia | 1991 | 2004 | 1 | 0.687 | 8 | |
| Latvia | 1991 | 2005 | 1 | 0.687 | 8 | |
| Latvia | 1991 | 2007 | 1 | 0.687 | 8 | |
| Latvia | 1991 | 2009 | 2 | 0.687 | 8 | |
| Latvia | 1991 | 2013 | No amendment | 0.687 | 8 | |
| Lesotho | 1993 | 1996 | In house | 2 | 1 | 8 |
| Lesotho | 1993 | 1997 | 2 | 1 | 8 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Lesotho | 1993 | 2001 | 2 | 1 | 6 | |
| Lesotho | 1993 | 2004 | 2 | 1 | 8 | |
| Lithuania | 1992 | 1996 | 1 | 2 | 0.697 | 10 |
| Lithuania | 1992 | 2002 | 2 | 0.697 | 10 | |
| Lithuania | 1992 | 2003 | 2 | 0.697 | 10 | |
| Lithuania | 1992 | 2004 | 3 | 0.697 | 10 | |
| Lithuania | 1992 | 2006 | 2 | 0.697 | 10 | |
| Luxembourg | 1868 | 1919 | In house | 3 | 0.687 | 7 |
| Luxembourg | 1868 | 1948 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 1956 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 1972 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 1979 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 1983 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 1988 | No amendment | 0.687 | 10 | |
| Luxembourg | 1868 | 1989 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 1994 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 1996 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 1998 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 1999 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2000 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2003 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2004 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2005 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 2006 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2007 | 2 | 0.687 | 10 | |
| Luxembourg | 1868 | 2008 | 1 | 0.687 | 10 | |
| Luxembourg | 1868 | 2009 | 1 | 0.687 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Macedonia | 1991 | 1992 | 1 | 1 | 0.687 | 6 |
| Macedonia | 1991 | 1998 | 1 | 0.687 | 6 | |
| Macedonia | 1991 | 2001 | 2 | 0.687 | 6 | |
| Macedonia | 1991 | 2003 | 1 | 0.687 | 9 | |
| Macedonia | 1991 | 2005 | 1 | 0.687 | 9 | |
| Macedonia | 1991 | 2009 | 1 | 0.687 | 9 | |
| Macedonia | 1991 | 2011 | 1 | 0.687 | 9 | |
| Malawi | 1994 | 1995 | 1 | 2 | 0.677 | 6 |
| Malawi | 1994 | 1997 | 1 | 0.677 | 6 | |
| Malawi | 1994 | 1998 | 1 | 0.677 | 6 | |
| Malawi | 1994 | 1999 | 1 | 0.677 | 6 | |
| Malawi | 1994 | 2004 | 1 | 0.677 | 6 | |
| Malawi | 1994 | 2010 | 2 | 0.677 | 6 | |
| Malaysia | 1957 | 1958 | 1 | 1 | 0.947 | 10 |
| Malaysia | 1957 | 1959 | No amendment? | 0.947 | 10 | |
| Malaysia | 1957 | 1960 | 2 | 0.947 | 10 | |
| Malaysia | 1957 | 1961 | No amendment? | 0.947 | 10 | |
| Malaysia | 1957 | 1962 | 3 | 0.947 | 10 | |
| Malaysia | 1957 | 1963 | 3 | 0.947 | 10 | |
| Malaysia | 1957 | 1964 | 1 | 0.947 | 10 | |
| Malaysia | 1957 | 1965 | 2 | 0.947 | 10 | |
| Malaysia | 1957 | 1966 | 1 | 0.947 | 10 | |
| Malaysia | 1957 | 1968 | 1 | 0.947 | 10 | |
| Mauritius | 1968 | 1969 | In house | 3 | 0.677 | 9 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Mauritius | 1968 | 1973 | 3 | 0.677 | 9 | |
| Mauritius | 1968 | 1975 | 1 | 0.677 | 9 | |
| Mauritius | 1968 | 1982 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 1983 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 1985 | 2 | 0.677 | 10 | |
| Mauritius | 1968 | 1986 | 1 | 0.677 | 10 | |
| Mauritius | 1968 | 1990 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 1991 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 1992 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 1994 | 1 | 0.677 | 10 | |
| Mauritius | 1968 | 1995 | 2 | 0.677 | 10 | |
| Mauritius | 1968 | 1996 | 1 | 0.677 | 10 | |
| Mauritius | 1968 | 1997 | 1 | 0.677 | 10 | |
| Mauritius | 1968 | 2000 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 2001 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 2003 | 3 | 0.677 | 10 | |
| Mauritius | 1968 | 2008 | 1 | 0.677 | 10 | |
| Mauritius | 1968 | 2011 | 1 | 0.677 | 10 | |
| Mexico | 1917 | 1997 | 2 | 1 | 1.232 | 6 |
| Mexico | 1917 | 1999 | 2 | 1.232 | 6 | |
| Mexico | 1917 | 2000 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2001 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2002 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2003 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2004 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2005 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2006 | 2 | 1.232 | 8 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Mexico | 1917 | 2007 | 2 | 1.232 | 8 | |
| Mexico | 1917 | 2008 | 2 | 1.232 | 8 | |
| Mexico | 1917 | 2009 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2010 | 1 | 1.232 | 8 | |
| Mexico | 1917 | 2011 | 2 | 1.232 | 8 | |
| Mexico | 1917 | 2012 | 3 | 1.232 | 8 | |
| Mexico | 1917 | 2013 | 2 | 1.232 | 8 | |
| Moldova | 1994 | 1996 | 1 | 2 | 0.687 | 7 |
| Moldova | 1994 | 2000 | 3 | 0.687 | 7 | |
| Moldova | 1994 | 2001 | 2 | 0.687 | 8 | |
| Moldova | 1994 | 2002 | 2 | 0.687 | 8 | |
| Moldova | 1994 | 2003 | 1 | 0.687 | 8 | |
| Moldova | 1994 | 2006 | 1 | 0.687 | 9 | |
| Mongolia | 1992 | 2001 | In house | 3 | 0.76 | 10 |
| Mozambique | 2004 | 2007 | In house | 1 | 0.67 | 5 |
| Montenegro | 2007 | 2013 | In house | 3 | 0.697 | 8 |
| Namibia | 1990 | 1998 | In house | 1 | 0.807 | 6 |
| Namibia | 1990 | 2010 | 1 | 0.807 | 6 | |
| Nepal | 2007 | 2007 | 1 | 3 | 0.677 | 6 |
| Nepal | 2007 | 2008 | 3 | 0.677 | 6 | |
| Nepal | 2007 | 2010 | 1 | 0.677 | 6 | |
| Nepal | 2007 | 2011 | 1 | 0.677 | 6 | |
| Nepal | 2007 | 2012 | 2 | 0.677 | 6 | |
| Netherlands | 1848 | 1917 | 1 | 2 | 1.331 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Netherlands | 1848 | 1922 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1938 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1946 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1947 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1948 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1953 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1956 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1963 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1972 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1983 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1987 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1995 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 1999 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 2000 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 2002 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 2005 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 2006 | 1 | 1.331 | 10 | |
| Netherlands | 1848 | 2008 | 1 | 1.331 | 10 | |
| New Zealand | 1852 | 1857 | In house | 1 | 0.5 | 10 |
| New Zealand | 1852 | 1863 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1881 | 2 | 0.5 | 9 | |
| New Zealand | 1852 | 1891 | 2 | 0.5 | 9 | |
| New Zealand | 1852 | 1892 | 3 | 0.5 | 9 | |
| New Zealand | 1852 | 1893 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1894 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1902 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1907 | 3 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| New Zealand | 1852 | 1908 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1909 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1910 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1911 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1912 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1913 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1917 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1923 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1925 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1927 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1928 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1930 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1933 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1935 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1936 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1947 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1949 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1950 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1951 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1952 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1953 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1954 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1955 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1956 | 3 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| New Zealand | 1852 | 1957 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1958 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1959 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1960 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1961 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1963 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1965 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1967 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1968 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1969 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1970 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1971 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1972 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1973 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1974 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1975 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1976 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1977 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1978 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1979 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1980 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1981 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1982 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1983 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1985 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1986 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1987 | 1 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| New Zealand | 1852 | 1988 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1989 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1990 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1991 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1992 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1993 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 1994 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1995 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1996 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1997 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 1998 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 1999 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 2000 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2001 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 2002 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 2003 | 3 | 0.5 | 10 | |
| New Zealand | 1852 | 2004 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 2005 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2006 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 2007 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2008 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2009 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2010 | 2 | 0.5 | 10 | |
| New Zealand | 1852 | 2011 | 1 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| New Zealand | 1852 | 2012 | 1 | 0.5 | 10 | |
| New Zealand | 1852 | 2013 | 1 | 0.5 | 10 | |
| Nicaragua | 1987 | 1994 | 1 | No amendment | 0.61 | 6 |
| Nicaragua | 1987 | 1995 | 3 | 0.61 | 8 | |
| Nicaragua | 1987 | 2000 | 2 | 0.61 | 8 | |
| Nicaragua | 1987 | 2005 | 1 | 0.61 | 8 | |
| Nicaragua | 1987 | 2007 | 1 | 0.61 | 9 | |
| Norway | 1814 | 1898 | 2 | 2 | 0.677 | 10 |
| Norway | 1814 | 1899 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1901 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1902 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1903 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1905 | 3 | 0.677 | 10 | |
| Norway | 1814 | 1907 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1908 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1910 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1911 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1913 | 2 | 0.677 | 10 | |
| Norway | 1814 | 1914 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1916 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1917 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1919 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1920 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1922 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1923 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1925 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1926 | 1 | 0.677 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Norway | 1814 | 1928 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1929 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1931 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1932 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1935 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1938 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1946 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1948 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1951 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1952 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1954 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1956 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1959 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1962 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1964 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1967 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1972 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1975 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1976 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1978 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1980 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1984 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1986 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1988 | 1 | 0.677 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Norway | 1814 | 1990 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1992 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1994 | 1 | 0.677 | 10 | |
| Norway | 1814 | 1995 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2003 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2004 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2006 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2007 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2010 | 1 | 0.677 | 10 | |
| Norway | 1814 | 2012 | 1 | 0.677 | 10 | |
| Pakistan | 2002 | 2010 | 2 | 3 | 0.848 | 6 |
| Pakistan | 2002 | 2011 | 2 | 0.848 | 6 | |
| Pakistan | 2002 | 2012 | 2 | 0.848 | 6 | |
| Panama | 1972 | 1993 | 1 | 1 | 1.01 | 8 |
| Panama | 1972 | 1994 | 1 | 1.01 | 9 | |
| Panama | 1972 | 2004 | 2 | 1.01 | 9 | |
| Paraguay | 1992 | 2011 | 1 | 1 | 1.102 | 8 |
| Peru | 1993 | 2000 | In house | 3 | 0.99 | 5 |
| Peru | 1993 | 2002 | 1 | 2 | 0.99 | 9 |
| Peru | 1993 | 2004 | 1 | 0.99 | 9 | |
| Peru | 1993 | 2005 | 1 | 0.99 | 9 | |
| Peru | 1993 | 2009 | 1 | 0.99 | 9 | |
| Poland | 1997 | 2006 | 6 | 1 | 0.828 | 10 |
| Poland | 1997 | 2009 | 1 | 0.828 | 10 | |
| Portugal | 1976 | 1982 | 1 | 1 | 0.677 | 10 |
| Portugal | 1976 | 1989 | 2 | 0.677 | 10 | |
| Portugal | 1976 | 1992 | 2 | 0.677 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Portugal | 1976 | 1997 | 2 | 0.677 | 10 | |
| Portugal | 1976 | 2001 | 2 | 0.677 | 10 | |
| Portugal | 1976 | 2004 | 2 | 0.677 | 10 | |
| Portugal | 1976 | 2005 | 2 | 0.677 | 10 | |
| Romania | 1991 | 2003 | In house | 3 | 1.249 | 8 |
| Senegal | 2001 | 2003 | In house | 1 | 1 | 8 |
| Senegal | 2001 | 2006 | 1 | 1 | 8 | |
| Senegal | 2001 | 2007 | 1 | 1 | 7 | |
| Senegal | 2001 | 2008 | 2 | 1 | 7 | |
| Senegal | 2001 | 2009 | 1 | 1 | 7 | |
| Senegal | 2001 | 2012 | 1 | 1 | 7 | |
| Sierra Leone | 1996 | 2008 | In house | 2 | 0.697 | 7 |
| Slovak Republic | 1992 | 1998 | 1 | 2 | 0.61 | 9 |
| Slovak Republic | 1992 | 1999 | 3 | 0.61 | 9 | |
| Slovak Republic | 1992 | 2001 | 3 | 0.61 | 9 | |
| Slovak Republic | 1992 | 2004 | 1 | 0.61 | 9 | |
| Slovak Republic | 1992 | 2005 | 1 | 0.61 | 9 | |
| Slovak Republic | 1992 | 2006 | 1 | 0.61 | 10 | |
| Slovak Republic | 1992 | 2010 | 1 | 0.61 | 10 | |
| Slovak Republic | 1992 | 2011 | 3 | 0.61 | 10 | |
| Slovak Republic | 1992 | 2012 | 1 | 0.61 | 10 | |
| Slovenia | 1991 | 1997 | In house | 2 | 0.687 | 10 |
| Slovenia | 1991 | 2000 | 3 | 0.687 | 10 | |
| Slovenia | 1991 | 2003 | 3 | 0.687 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Slovenia | 1991 | 2004 | 1 | 0.687 | 10 | |
| Slovenia | 1991 | 2006 | 2 | 0.687 | 10 | |
| Slovenia | 1991 | 2013 | 1 | 0.687 | 10 | |
| Solomon Islands | 1978 | 1982 | In house | 1 | 0.697 | 7 |
| Solomon Islands | 1978 | 1983 | 2 | 0.697 | 7 | |
| Solomon Islands | 1978 | 1989 | 1 | 0.697 | 7 | |
| Solomon Islands | 1978 | 1992 | 1 | 0.697 | 8 | |
| Solomon Islands | 1978 | 2008 | 1 | 0.697 | 8 | |
| Solomon Islands | 1978 | 2009 | 2 | 0.697 | 8 | |
| South Africa | 1996 | 1997 | 3 | 1 | 0.717 | 9 |
| South Africa | 1996 | 1998 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 1999 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2001 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2002 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2003 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2005 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2007 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2008 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2009 | 1 | 0.717 | 9 | |
| South Africa | 1996 | 2012 | 1 | 0.717 | 9 | |
| South Korea | 1948 | 1960 | 1 | 3 | 1.197 | 8 |
| Spain | 1978 | 1992 | 2 | 2 | 0.648 | 10 |
| Spain | 1978 | 2011 | 2 | 0.648 | 10 | |
| Surinam | 1987 | 1992 | In house | 2 | 0.667 | 5 |
| Sweden | 1974 | 1975 | 2 | 1 | 0.99 | 10 |
| Sweden | 1974 | 1976 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1977 | 1 | 0.99 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Sweden | 1974 | 1978 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1979 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1981 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1982 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1983 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1984 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1985 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1986 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1987 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1988 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1989 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1990 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1991 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1992 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1993 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1994 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1995 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1996 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1997 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 1998 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 2000 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 2001 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 2002 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 2003 | 1 | 0.99 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Sweden | 1974 | 2009 | 1 | 0.99 | 10 | |
| Sweden | 1974 | 2011 | 2 | 0.99 | 10 | |
| Sweden | 1974 | 2012 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2000 | 2 | 1 | 0.99 | 10 |
| Switzerland | 1999 | 2001 | 2 | 0.99 | 10 | |
| Switzerland | 1999 | 2002 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2003 | 2 | 0.99 | 10 | |
| Switzerland | 1999 | 2004 | 2 | 0.99 | 10 | |
| Switzerland | 1999 | 2005 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2006 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2007 | No amendment | 0.99 | 10 | |
| Switzerland | 1999 | 2008 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2009 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2010 | 2 | 0.99 | 10 | |
| Switzerland | 1999 | 2011 | No amendment | 0.99 | 10 | |
| Switzerland | 1999 | 2012 | 1 | 0.99 | 10 | |
| Switzerland | 1999 | 2013 | 1 | 0.99 | 10 | |
| Taiwan | 1947 | 2000 | 1 | 3 | 0.75 | 9 |
| Taiwan | 1947 | 2005 | 3 | 1.27 | 10 | |
| Trinidad and Tobago | 1976 | 1978 | In house | 1 | 0.923 | 8 |
| Trinidad and Tobago | 1976 | 1979 | 1 | 0.923 | 8 | |
| Trinidad and Tobago | 1976 | 1981 | 1 | 0.923 | 8 | |
| Trinidad and Tobago | 1976 | 1982 | 1 | 0.923 | 8 | |
| Trinidad and Tobago | 1976 | 1983 | 1 | 0.923 | 8 | |
| Trinidad and Tobago | 1976 | 1987 | 1 | 0.923 | 9 | |
| Trinidad and Tobago | 1976 | 1988 | 1 | 0.923 | 9 | |
| Trinidad and Tobago | 1976 | 1994 | 1 | 0.923 | 9 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| Trinidad and Tobago | 1976 | 1995 | 1 | 0.923 | 9 | |
| Trinidad and Tobago | 1976 | 1996 | 2 | 0.923 | 9 | |
| Trinidad and Tobago | 1976 | 1999 | 1 | 0.923 | 10 | |
| Trinidad and Tobago | 1976 | 2000 | 1 | 0.923 | 10 | |
| Trinidad and Tobago | 1976 | 2006 | 1 | 0.923 | 10 | |
| Trinidad and Tobago | 1976 | 2007 | 1 | 0.923 | 10 | |
| Turkey | 1982 | 1987 | 4 | 2 | 1.187 | 7 |
| Turkey | 1982 | 1993 | 1 | 1.11 | 8 | |
| Turkey | 1982 | 1995 | 2 | 1.11 | 8 | |
| Turkey | 1982 | 1999 | 1 | 1.11 | 7 | |
| Turkey | 1982 | 2001 | 2 | 1.11 | 7 | |
| Turkey | 1982 | 2002 | 1 | 1.11 | 7 | |
| Turkey | 1982 | 2004 | 2 | 1.11 | 7 | |
| Turkey | 1982 | 2005 | 1 | 1.11 | 7 | |
| Turkey | 1982 | 2006 | 1 | 1.11 | 7 | |
| Turkey | 1982 | 2007 | 3 | 1.11 | 7 | |
| Turkey | 1982 | 2010 | 2 | 1.11 | 7 | |
| Turkey | 1982 | 2011 | 1 | 1.11 | 9 | |
| Ukraine | 1996 | 2004 | 1 | 3 | 0.687 | 6 |
| Ukraine | 1996 | 2010 | 3 | 0.687 | 6 | |
| Ukraine | 1996 | 2011 | 1 | 0.687 | 6 | |
| Ukraine | 1996 | 2013 | 1 | 0.687 | 6 | |
| United Kingdom | 1297 | 1911 | In house | 3 | 0.776 | 8 |
| United Kingdom | 1297 | 1914 | 1 | 0.5 | 8 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| United Kingdom | 1297 | 1918 | 3 | 0.5 | 8 | |
| United Kingdom | 1297 | 1925 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1947 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1948 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1949 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 1950 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1953 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1955 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1958 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 1962 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1963 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1967 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1968 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1969 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1971 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1972 | 3 | 0.5 | 10 | |
| United Kingdom | 1297 | 1973 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1975 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1976 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1977 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1978 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1979 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1980 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1981 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1982 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1983 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1984 | 1 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| United Kingdom | 1297 | 1985 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1986 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1987 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1988 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1989 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1990 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1991 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1992 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1993 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1994 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1995 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1996 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1997 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 1998 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 1999 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 2000 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2001 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2002 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2003 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 2004 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2005 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 2006 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 2007 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2008 | 1 | 0.5 | 10 |
| Country | Constitution year | Amendment year | Responses | Median value | VP rigid | POLITY2 |
|---|---|---|---|---|---|---|
| United Kingdom | 1297 | 2009 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2010 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2010 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2011 | 2 | 0.5 | 10 | |
| United Kingdom | 1297 | 2012 | 1 | 0.5 | 10 | |
| United Kingdom | 1297 | 2013 | 1 | 0.5 | 10 | |
| United States | 1789 | 1865 | 1 | 3 | 1.489 | 8 |
| United States | 1789 | 1868 | 2 | 1.489 | 8 | |
| United States | 1789 | 1870 | 2 | 1.489 | 8 | |
| United States | 1789 | 1913 | 2 | 1.489 | 10 | |
| United States | 1789 | 1919 | 1 | 1.489 | 10 | |
| United States | 1789 | 1920 | 2 | 1.489 | 10 | |
| United States | 1789 | 1933 | 1 | 1.489 | 10 | |
| United States | 1789 | 1951 | 2 | 1.489 | 10 | |
| United States | 1789 | 1961 | 1 | 1.489 | 10 | |
| United States | 1789 | 1964 | 2 | 1.489 | 10 | |
| United States | 1789 | 1967 | 1 | 1.489 | 8 | |
| United States | 1789 | 1971 | 1 | 1.489 | 8 | |
| United States | 1789 | 1992 | 1 | 1.489 | 10 | |
| Uruguay | 1985 | 1989 | 1 | 1 | 0.5 | 10 |
| Uruguay | 1985 | 1994 | 1 | 0.5 | 10 | |
| Uruguay | 1985 | 1996 | 3 | 0.5 | 10 | |
| Uruguay | 1985 | 2004 | 1 | 0.5 | 10 | |
| Zambia | 1991 | 2009 | In house | 1 | 0.697 | 7 |