Year	% (modeled ILO estimate)
1991	58.941
1992	57.725
1993	56.094
1994	55.695
1995	56.319
1996	55.745
1997	56.444
1998	57.124
1999	57.165
2000	57.677
2001	55.456
2002	53.221
2003	50.979
2004	48.736
2005	46.503
2006	44.291
2007	42.108
2008	39.96
2009	37.856
2010	35.801
2011	35.883
2012	35.714
2013	35.598
2014	34.848
2015	34.541
2016	34.304
2017	34.197
2018	34.347
2019	34.082
2020	33.752
2021	33.302
2022	32.991
2023	32.814