Year Percent
1950 9.508
1951 8.898
1952 7.677
1953 6.532
1954 5.609
1955 5
1956 4.762
1957 4.961
1958 5.601
1959 6.574
1960 7.65
1961 8.588
1962 9.126
1963 9.154
1964 8.827
1965 8.348
1966 7.934
1967 7.734
1968 7.805
1969 8.065
1970 8.44
1971 8.779
1972 8.742
1973 8.17
1974 7.243
1975 6.154
1976 5.203
1977 4.993
1978 5.905
1979 7.633
1980 9.474
1981 10.74
1982 11.044
1983 10.388
1984 9.077
1985 7.653
1986 6.47
1987 5.454
1988 4.474
1989 3.55
1990 2.699
1991 1.962
1992 1.423
1993 1.155
1994 1.171
1995 1.478
1996 2.019
1997 2.622
1998 3.157
1999 3.663
2000 4.001
2001 4.316
2002 5.498
2003 8.077
2004 11.397
2005 14.314
2006 15.941
2007 15.925
2008 14.529
2009 12.38
2010 10.233
2011 8.503
2012 7.113
2013 5.913
2014 4.887
2015 3.954
2016 3.08
2017 2.376
2018 1.945
2019 1.767
2020 1.728
2021 1.71
2022 1.675
2023 1.618
2024 1.532
2025 1.444
2026 1.38
2027 1.329
2028 1.275
2029 1.218
2030 1.162
2031 1.11
2032 1.06
2033 1.004
2034 0.945
2035 0.884
2036 0.827
2037 0.779
2038 0.746
2039 0.727
2040 0.717
2041 0.709
2042 0.698
2043 0.685
2044 0.668
2045 0.651
2046 0.634
2047 0.617
2048 0.598
2049 0.578
2050 0.557
2051 0.535
2052 0.514
2053 0.492
2054 0.471
2055 0.45
2056 0.428
2057 0.407
2058 0.386
2059 0.366
2060 0.345
2061 0.325
2062 0.306
2063 0.287
2064 0.269
2065 0.251
2066 0.233
2067 0.216
2068 0.199
2069 0.181
2070 0.164
2071 0.147
2072 0.129
2073 0.111
2074 0.093
2075 0.075
2076 0.057
2077 0.039
2078 0.021
2079 0.002
2080 -0.017
2081 -0.034
2082 -0.052
2083 -0.068
2084 -0.083
2085 -0.098
2086 -0.111
2087 -0.124
2088 -0.134
2089 -0.143
2090 -0.151
2091 -0.157
2092 -0.163
2093 -0.168
2094 -0.172
2095 -0.176
2096 -0.178
2097 -0.18
2098 -0.18
2099 -0.178