Year	% of total
1990	11.768747953158302
1991	11.864042661852913
1992	11.99449511008601
1993	12.018192532968184
1994	12.059058525752341
1995	11.749810655928266
1996	11.42088312071072
1997	10.976593040277606
1998	10.047395283788067
1999	9.311349014563964
2000	8.583846106410203
2001	8.64053829704221
2002	8.049135750548626
2003	8.161876169794125
2004	8.00311092827257
2005	7.792628192513223
2006	8.295782088451435
2007	8.378358355818438
2008	8.609778846631517