Year	% net
1975	35.04555
1976	35.7556
1977	38.69145
1978	46.87701
1979	54.01859
1980	58.26259
1981	57.59019
1982	58.59175
1985	50.94654
1987	50.41282
1988	48.07603
1989	46.65439
1993	41.94431
1999	36.71281
2000	39.02664
2003	40.54876
2004	46.96191
2007	49.797