Year	% of cohort
1997	39.232551574707
1998	44.055908203125
2000	54.7356986999512
2001	63.5925598144531
2002	55.0177612304688
2003	53.5175094604492
2004	56.9225006103516
2005	55.0913505554199
2006	54.4838905334473
2007	54.4634895324707
2010	61.3429718017578
2011	65.9485626220703
2012	64.2295989990234
2015	73.4880523681641
2016	76.2490310668945
2017	83.5045471191406
2018	79.760498046875
2019	79.6955184936523