Year	per 1,000
1990	2.993178298322225
1991	2.9946049820980196
1992	2.8908332589185015
1993	2.8215182421753133
1994	2.712029197612157
1995	2.5986600854266295
1996	2.5595723687108936
1997	2.5283374073954823
1998	2.4691487598562456
1999	2.4319262556078365
2000	2.3714226528314546
2001	2.2938995297390705
2002	2.1503547735217383
2003	2.0663853196266233
2004	1.982755454789493
2005	1.8832728771262321
2006	1.7867678235823226
2007	1.706093269701432
2008	1.6154949141839707
2009	1.5423539362314436
2010	1.4475780745482674
2011	1.373234228709466
2012	1.3079623245672738
2013	1.2362016267132596
2014	1.177302272486261
2015	1.1652341121024763
2016	1.154228054680471
2017	1.112497532263301
2018	1.080482853000618
2019	1.0645099144322139
2020	1.0622252519030808
2021	1.0704498311252613
2022	1.098657754707513