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

r<=21 208 210.9 0.041 0.041
r=22 5258 5135.9 2.903 2.944
r=23 23045 23103.6 0.149 3.093
r=24 11489 11549.5 0.317 3.410

chi-square = 3.410 with df = 3; p-value = 0.332658