Year Percent 1950 12.42686 1955 14.50807 1960 15.30665 1965 16.22982 1970 15.12258 1975 14.70352 1980 15.12162 1985 15.98135 1990 16.39062 1995 15.38688 2000 13.383 2005 13.55402 2010 13.54155 2015 13.6184 2020 12.82513 2025 11.84101 2030 10.89412 2035 10.29132 2040 9.88923 2045 9.44366 2050 8.84534 2055 8.18262 2060 7.59655 2065 7.14316 2070 6.77026 2075 6.44175 2080 6.10682 2085 5.79356 2090 5.53227 2095 5.33918 2100 5.19602