Year	Number
1996	1.37154483795166
1998	1.25270414352417
2000	1.14826655387878
2002	1.21802008152008
2003	1.11910235881805
2004	1.12566697597504
2005	1.06187832355499
2006	1.00923573970795
2007	1.02880275249481
2008	1.05923020839691
2009	1.08558297157288
2010	1.06266355514526
2011	1.08125162124634
2012	0.955447733402252
2013	0.912236094474792
2014	0.909682035446167
2015	0.892668664455414
2016	0.859336078166962
2017	0.821442186832428
2018	0.806138753890991
2019	0.745713293552399
2020	0.721121430397034
2021	0.74234664440155
2022	0.729021430015564