Year Percent
1950 1.451
1951 1.7
1952 2.179
1953 2.604
1954 2.944
1955 3.173
1956 3.278
1957 3.245
1958 3.074
1959 2.789
1960 2.433
1961 2.065
1962 1.753
1963 1.557
1964 1.474
1965 1.448
1966 1.412
1967 1.338
1968 1.212
1969 1.036
1970 0.847
1971 0.682
1972 0.537
1973 0.394
1974 0.267
1975 0.14
1976 0.025
1977 0.004
1978 0.148
1979 0.449
1980 0.836
1981 1.215
1982 1.516
1983 1.696
1984 1.754
1985 1.753
1986 1.75
1987 1.711
1988 1.596
1989 1.419
1990 1.199
1991 0.974
1992 0.809
1993 0.757
1994 0.814
1995 0.931
1996 1.045
1997 1.107
1998 1.098
1999 1.018
2000 0.9
2001 0.784
2002 0.692
2003 0.636
2004 0.614
2005 0.611
2006 0.606
2007 0.572
2008 0.495
2009 0.376
2010 0.235
2011 0.098
2012 -0.012
2013 -0.08
2014 -0.102
2015 -0.101
2016 -0.094
2017 -0.089
2018 -0.086
2019 -0.083
2020 -0.08
2021 -0.073
2022 -0.062
2023 -0.045
2024 -0.026
2025 -0.004
2026 0.016
2027 0.029
2028 0.032
2029 0.023
2030 0.01
2031 -0.008
2032 -0.029
2033 -0.052
2034 -0.079
2035 -0.108
2036 -0.139
2037 -0.172
2038 -0.204
2039 -0.236
2040 -0.269
2041 -0.301
2042 -0.334
2043 -0.363
2044 -0.392
2045 -0.419
2046 -0.443
2047 -0.466
2048 -0.484
2049 -0.499
2050 -0.51
2051 -0.52
2052 -0.526
2053 -0.528
2054 -0.528
2055 -0.525
2056 -0.52
2057 -0.513
2058 -0.506
2059 -0.499
2060 -0.489
2061 -0.48
2062 -0.468
2063 -0.457
2064 -0.446
2065 -0.433
2066 -0.42
2067 -0.408
2068 -0.398
2069 -0.391
2070 -0.384
2071 -0.377
2072 -0.371
2073 -0.365
2074 -0.358
2075 -0.353
2076 -0.349
2077 -0.345
2078 -0.346
2079 -0.349
2080 -0.354
2081 -0.358
2082 -0.365
2083 -0.374
2084 -0.381
2085 -0.39
2086 -0.4
2087 -0.41
2088 -0.422
2089 -0.438
2090 -0.453
2091 -0.468
2092 -0.48
2093 -0.491
2094 -0.5
2095 -0.504
2096 -0.507
2097 -0.508
2098 -0.506
2099 -0.502