cohort,grade_1,grade_2,grade_3,grade_4,grade_5,grade_6,grade_7,grade_8,grade_9,grade_10,grade_11,grade_12,diff,percent_change
2007-2018,1172659,1031821,1003394,1002645,957203,935446,902099,935624,950512,1104749,892784,643802,,
2008-2019,1122114,1003071,972668,974860,939025,909095,875311,931766,905066,1075925,862009,640714,-481400,-43%
2009-2020,1105186,994410,957209,966349,923562,804517,884994,952628,894113,1033799,861035,628190,-476996,-43%
2010-2021,1116899,1003353,967373,964630,929735,800799,899622,971367,820836,1045424,867783,750478,-366421,-33%
2011-2022,1177089,1074788,1025185,1036378,979360,947015,924167,995994,930960,1104452,954069,775630,-401459,-34%