Year	% of total
1992	28.75970470470471
1993	22.691601016518423
1994	26.765881161377447
1995	33.81433042212518
1996	34.89190442726634
1997	32.92923850574713
1998	27.29683888511217
1999	34.12555102040816
2000	45.56709800190295
2001	44.06977578475336
2002	44.28507130124777
2003	48.00080142475512
2004	45.13704450041981
2005	44.215502727981296
2006	43.17596774193549
2007	50.13324753974262
2008	45.51460183767229
2009	42.72415739948674
2010	45.28453968253968
2011	52.589239864864865
2012	50.963000838222975
2013	43.75802294792586
2014	43.5245211786372
2015	42.765103884372174
2016	37.652232142857144