Year	% of total
1971	98.38182300370752
1972	98.52384676624591
1973	98.53232425040966
1974	98.70848084877233
1975	98.90610852060395
1976	98.88436220837319
1977	99.01320737885001
1978	99.04265314183615
1979	99.34582241234362
1980	99.41811944171096
1981	99.3673513348344
1982	99.4313306245819
1983	99.58306093011429
1994	94.22567013679046
1995	94.54430039376219
1996	93.48240804264002
1997	93.16714026997033
1998	94.88346803226364
1999	94.7972181654043
2000	93.89153113368538
2001	94.3445501374618
2002	94.33330219446842
2003	94.88612058566746
2004	94.98405042016542
2005	95.1033438525165
2006	95.34356584784167
2007	95.343126272047
2008	94.72453161391185
2009	94.92692512796167
2010	93.97148467941803
2011	94.31188882654288
2012	93.28220408099162
2013	93.6382381470521
2014	93.17288162006344