2020 2019 2018
A+ 37457 5.07 35118 4.25 33046 4.44
A 105345 14.28 109316 13.24 107045 14.38
B+ 147801 20.01 154001 18.65 151928 20.41
B 153860 20.83 162892 19.73 160613 21.57
C+ 98704 13.36 107165 12.98 109509 14.71
C 14612 1.98 17823 2.15 19376 2.6