Year	Percent
1960-01-01	1.98840080872216
1961-01-01	4.71160874619984
1962-01-01	11.01630006350320
1963-01-01	12.92801598224980
1964-01-01	19.24505104382900
1965-01-01	7.31707244304524
1966-01-01	10.68664741841390
1967-01-01	3.32022094636190
1977-01-01	30.31674127259290
1978-01-01	43.74999828536060
1979-01-01	44.44445580437440
1980-01-01	58.52842608936470
1981-01-01	51.79324160101080
1982-01-01	50.24322638967600
1983-01-01	83.95004619370350
1984-01-01	30.85239707709090
1985-01-01	31.99462902407030
1986-01-01	22.12840118766460
1987-01-01	18.29776822323040
1988-01-01	25.72550908528430
1989-01-01	20.75819503344850
1990-01-01	15.51072199425300
1991-01-01	6.80877887943638
1992-01-01	3.94771176824033
1993-01-01	4.04285291076943
1994-01-01	1.55265627495782
1995-01-01	1.65123150116651
1996-01-01	2.26041898267296
1997-01-01	1.81543080282247
1998-01-01	1.65924170953426
1999-01-01	3.23183260906467
2000-01-01	5.13647123245151
2001-01-01	6.40508550386865
2002-01-01	5.19702230216630
2003-01-01	2.05566329753740
2004-01-01	3.15819324298464
2005-01-01	3.98704782806592
2006-01-01	6.68707906136661
2007-01-01	5.05155736492145
2008-01-01	12.69439427758780
2009-01-01	12.00312984617430
2010-01-01	5.39673113167484
2011-01-01	4.00102664343116
2012-01-01	5.18589988750705
2013-01-01	3.87227923748240
2014-01-01	2.04461481539337
2015-01-01	1.63305558181333
2016-01-01	1.69692761997740
2017-01-01	1.76041559180606