Year	% of cohort
1989	59.6912117004395
1990	76.8960723876953
1991	74.9815979003906
1992	72.8418197631836
1993	74.1594314575195
1994	67.8008804321289
1995	63.0207595825195
1996	60.9145317077637
1997	64.9580688476562
1998	65.9269866943359
2001	53.6755599975586
2004	51.0931091308594
2005	58.702449798584
2006	62.5539207458496
2008	80.4659729003906
2012	75.3138580322266
2016	67.9757232666016