Year	% net
1974	2.06289
1976	2.45299
1977	3.11367
1978	3.78873
1979	4.73081
1981	5.19651
1990	7.86787
1991	8.47859
1997	6.99573
1999	6.74089
2001	6.55139
2002	6.84434
2003	7.59309
2004	9.32465
2005	10.33223
2007	10.90372
2008	11.62732
2009	11.7602
2010	12.5669
2011	13.64281
2014	17.78033
2015	19.43599
2017	22.96816