PERIOD	VALUE
1997	10902
1998	13437
1999	14236
2000	15366
2001	17484
2002	20258
2003	22656
2004	24383
2005	28428
2006	33331
2007	36580
2008	33600
2009	35714
2010	35422
2011	31238
2012	32339
2013	35586
2014	39318
2015	43804
2016	46947
2017	52524
2018	56643