Year	Number
1960	20028
1961	20603
1962	21236
1963	21922
1964	22659
1965	23435
1966	24255
1967	25120
1968	26022
1969	26960
1970	27942
1971	28967
1972	30034
1973	31138
1974	32271
1975	33425
1976	34586
1977	35738
1978	36874
1979	37990
1980	39088
1981	40169
1982	41239
1983	42299
1984	43341
1985	44366
1986	45387
1987	46415
1988	47467
1989	48547
1990	49714
1991	51023
1992	52466
1993	54061
1994	55815
1995	57734
1996	59818
1997	62068
1998	64481
1999	67066
2000	69831
2001	72788
2002	75951
2003	79303
2004	82829
2005	86521
2006	90385
2007	94413
2008	98600
2009	102946
2010	107446
2011	112106
2012	116937
2013	121917
2014	127125
2015	132622
2016	138380
2017	144471
2018	150955
2019	157882
2020	164481
2021	170429
2022	176608
2023	183795