Year	Number
1970	295600
1971	269900
1972	240600
1973	280400
1974	315800
1975	298600
1976	288700
1977	324400
1978	359800
1979	414200
1980	507800
1981	410600
1982	377000
1983	435900
1984	439500
1985	451000
1986	319600
1987	425500
1988	482300
1989	573900
1990	609700
1991	447300
1992	437500
1993	602200
2010	501520
2011	423655.325587164
2012	422016.887644915
2013	372972
2014	239124
2015	276689
2016	275587
2017	248964
2018	411989
2019	321243
2021	271314