Year	per 1,000
1990	18.820000476626593
1991	18.282280399971498
1992	18.20100130398121
1993	18.47375541663925
1994	25.55774061384429
1995	17.6995030653271
1996	17.668523823343595
1997	17.14675796394659
1998	16.82798869844297
1999	16.508379440094686
2000	15.77154241424679
2001	15.281963712214957
2002	14.797881495984957
2003	14.386200508880378
2004	13.93071537592928
2005	13.535302370588557
2006	13.141854673185387
2007	12.783387797821106
2008	12.586823623728295
2009	12.237171815847773
2010	12.511769389842742
2011	11.838074183446942
2012	11.663737707476292
2013	11.53898089334078
2014	11.382815696366436
2015	11.201519477231972
2016	10.978763730868552
2017	10.763920257192956
2018	10.524896733799798
2019	10.275815546665141
2020	10.02942234872687
2021	9.799426421591376
2022	9.624972054998764