Year	Percent
1961	4.76424
1962	6.06381
1963	1.72674
1964	1.65456
1965	3.82944
1966	3.32574
1967	2.90397
1968	4.24868
1969	3.16858
1970	2.36999
1971	3.63276
1972	3.30667
1973	2.56996
1974	3.67306
1975	2.74721
1976	3.64302
1977	6.23175
1978	28.58687
1979	24.54382
1980	25.99625
1981	22.58362
1982	23.65867
1983	21.23999
1984	30.12996
1985	32.50541
1986	37.38305
1987	23.68077
1988	20.43598
1989	22.08743
1990	22.84748
1991	16.39366
1992	11.65586
1993	7.64043
1994	9.17082
1995	6.89216
1996	3.3031
1997	3.53415
1998	1.16316
1999	-0.91179
2000	0.66875
2001	2.47518
2002	1.07379
2003	0.42623
2004	3.22137
2005	1.4442
2006	1.20029
2007	0.9309
2008	2.69028
2009	5.96681
2010	5.28185
2011	1.32508
2012	0.9507
2013	2.36072
2014	3.07298
2015	1.94976
2016	0.89597
2017	1.84462
2018	2.73541
2019	3.25795