RANK OBSERVED EXPECTED (O-E)^2/E SUM

r<=21 197 210.9 0.921 0.921
r=22 5085 5135.9 0.504 1.426
r=23 22986 23103.6 0.599 2.025
r=24 11732 11549.5 2.883 4.908

chi-square = 4.908 with df = 3; p-value = 0.178685