Year	Index
1980	26.614
1981	30.493
1982	29.137
1983	26.203
1984	23.418
1985	25.189
1986	19.17
1987	20.021
1988	18.344
1989	18.409
1990	30.021
1991	28.55
1992	28.486
1993	27.02
1994	27.453
1995	29.586
1996	31.555
1997	30.268
1998	24.704
1999	28.627
2000	37.975
2001	36.095
2002	37.181
2003	43.567
2004	49.277
2005	64.328
2006	69.707
2007	77.353
2008	95.067
2009	72.043
2010	78.025
2011	92.28
2012	98.161
2013	100
2014	99.802
2015	75.511
2016	69.361
2017	75.121
2018	84.755
2019	83.024
2020	84.841
2021	85.772
2022	87.593
2023	89.735
2024	92.369