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

r<=28 221 211.4 0.434 0.434
r=29 5177 5134.0 0.360 0.794
r=30 23057 23103.0 0.092 0.886
r=31 11545 11551.5 0.004 0.890

chi-square = 0.890 with df = 3; p-value = 0.828