Year	Index (Units)
1980	0.120
1981	0.133
1982	0.134
1983	0.143
1984	0.148
1985	0.148
1986	0.169
1987	0.211
1988	0.298
1989	0.431
1990	0.605
1991	0.924
1992	1.176
1993	1.561
1994	2.738
1995	3.748
1996	5.687
1997	10.263
1998	12.403
1999	13.594
2000	14.899
2001	16.302
2002	17.775
2003	19.548
2004	22.528
2005	26.401
2006	32.886
2007	41.949
2008	52.367
2009	60.792
2010	68.628
2011	76.821
2012	84.816
2013	90.867
2014	96.706
2015	100.752
2016	105.913
2017	114.058
2018	124.374
2019	133.918
2020	146.443
2021	160.341
2022	200.717
2023	235.123
2024	260.752
2025	274.910
2026	288.678
2027	303.105
2028	318.348
2029	334.391