Year Number 1970 20962356 1971 22124536 1972 23390560 1973 24659278 1974 26540612 1975 28042136 1976 29804982 1977 32848000 1978 36519376 1979 40566460 1980 42999056 1981 45121024 1982 46922152 1983 48084580 1984 49021096 1985 48788364 1986 48325260 1987 48605660 1988 49326400 1989 49695856 1990 50955324 1991 53036776 1992 54044740 1993 56662904 1994 58258760 1995 60164668 1996 59157372 1997 64437664 1998 66976024 1999 69515544 2000 73518400 2001 77315928 2002 83639448 2003 90206392 2004 95266920 2005 99200688 2006 103796552 2007 107630016 2008 111553920 2009 115526840 2010 119304328 2011 124471864 2012 129809336 2013 134174664 2014 136994416 2015 138931616 2016 142467600 2017 147362240 2018 152705120 2019 157905392 2020 162601104 2021 166873680 2022 170553952