Year	% (modeled ILO estimate)
1991	19.607
1992	19.853
1993	19.956
1994	19.788
1995	19.525
1996	19.283
1997	19.103
1998	18.753
1999	19.363
2000	19.098
2001	19.004
2002	18.881
2003	18.736
2004	18.465
2005	18.211
2006	17.666
2007	17.222
2008	16.758
2009	17.201
2010	17.054
2011	16.865
2012	22.056
2013	20.099
2014	24.726
2015	27.246
2016	29.863
2017	28.13
2018	27.397
2019	31.576
2020	25.238
2021	25.583
2022	25.115
2023	26.252