Year Percent
1950 2.294
1951 2.323
1952 2.376
1953 2.42
1954 2.457
1955 2.487
1956 2.513
1957 2.534
1958 2.551
1959 2.566
1960 2.578
1961 2.59
1962 2.6
1963 2.611
1964 2.621
1965 2.637
1966 2.659
1967 2.675
1968 2.676
1969 2.667
1970 2.658
1971 2.664
1972 2.697
1973 2.767
1974 2.871
1975 2.98
1976 3.081
1977 3.207
1978 3.39
1979 3.613
1980 3.829
1981 3.993
1982 4.089
1983 4.113
1984 4.066
1985 3.995
1986 3.914
1987 3.733
1988 3.379
1989 2.883
1990 2.317
1991 1.777
1992 1.388
1993 1.241
1994 1.325
1995 1.532
1996 1.732
1997 1.847
1998 1.841
1999 1.716
2000 1.539
2001 1.381
2002 1.263
2003 1.187
2004 1.156
2005 1.144
2006 1.13
2007 1.123
2008 1.137
2009 1.168
2010 1.209
2011 1.249
2012 1.271
2013 1.264
2014 1.228
2015 1.176
2016 1.123
2017 1.069
2018 1.011
2019 0.951
2020 0.89
2021 0.827
2022 0.766
2023 0.706
2024 0.65
2025 0.597
2026 0.545
2027 0.499
2028 0.461
2029 0.431
2030 0.406
2031 0.384
2032 0.364
2033 0.35
2034 0.339
2035 0.331
2036 0.324
2037 0.317
2038 0.308
2039 0.299
2040 0.288
2041 0.276
2042 0.261
2043 0.242
2044 0.217
2045 0.19
2046 0.16
2047 0.129
2048 0.094
2049 0.056
2050 0.016
2051 -0.025
2052 -0.066
2053 -0.108
2054 -0.15
2055 -0.191
2056 -0.233
2057 -0.273
2058 -0.312
2059 -0.348
2060 -0.382
2061 -0.415
2062 -0.446
2063 -0.475
2064 -0.501
2065 -0.525
2066 -0.547
2067 -0.567
2068 -0.586
2069 -0.603
2070 -0.618
2071 -0.632
2072 -0.644
2073 -0.653
2074 -0.662
2075 -0.668
2076 -0.673
2077 -0.676
2078 -0.675
2079 -0.672
2080 -0.667
2081 -0.661
2082 -0.654
2083 -0.645
2084 -0.636
2085 -0.625
2086 -0.615
2087 -0.604
2088 -0.594
2089 -0.586
2090 -0.578
2091 -0.572
2092 -0.566
2093 -0.561
2094 -0.558
2095 -0.556
2096 -0.556
2097 -0.558
2098 -0.564
2099 -0.573