Year	per 1,000
1990	10.111131367949636
1991	9.904795076200115
1992	9.763935272344671
1993	9.755890341970778
1994	10.578308025186224
1995	9.632900028677334
1996	9.677609544801394
1997	9.582489395126078
1998	9.589409653306378
1999	9.60976439026543
2000	9.440925187728658
2001	9.318374745660469
2002	9.112383943479577
2003	8.922550989277477
2004	8.806716805582482
2005	8.538396519406486
2006	8.263181509525433
2007	8.066358862605943
2008	7.9323051874097334
2009	7.643575457685383
2010	7.502468970324837
2011	7.287104277214357
2012	7.208430539884682
2013	7.0822749719027716
2014	6.95913247464604
2015	6.909712335514705
2016	6.799430682436381
2017	6.72163696333007
2018	6.671300885668062
2019	6.549348467266209
2020	6.472664705136253
2021	6.438482116599563
2022	6.448784299912305