Frequencies for first 10,000 rows of dfage variable in natl1971 dataset : Age of | Father | Freq. Percent Cum. ------------+----------------------------------- 15 | 1 0.01 0.01 16 | 3 0.03 0.04 17 | 50 0.50 0.54 18 | 148 1.48 2.02 19 | 256 2.56 4.58 20 | 389 3.89 8.47 21 | 523 5.23 13.70 22 | 619 6.19 19.89 23 | 710 7.10 26.99 24 | 679 6.79 33.78 25 | 571 5.71 39.49 26 | 534 5.34 44.83 27 | 564 5.64 50.47 28 | 517 5.17 55.64 29 | 394 3.94 59.58 30 | 350 3.50 63.08 31 | 310 3.10 66.18 32 | 244 2.44 68.62 33 | 227 2.27 70.89 34 | 179 1.79 72.68 35 | 156 1.56 74.24 36 | 151 1.51 75.75 37 | 122 1.22 76.97 38 | 112 1.12 78.09 39 | 87 0.87 78.96 40 | 72 0.72 79.68 41 | 72 0.72 80.40 42 | 60 0.60 81.00 43 | 47 0.47 81.47 44 | 41 0.41 81.88 45 | 39 0.39 82.27 46 | 32 0.32 82.59 47 | 27 0.27 82.86 48 | 14 0.14 83.00 49 | 16 0.16 83.16 50 | 13 0.13 83.29 51 | 5 0.05 83.34 52 | 14 0.14 83.48 53 | 3 0.03 83.51 54 | 6 0.06 83.57 55 | 4 0.04 83.61 56 | 7 0.07 83.68 57 | 3 0.03 83.71 58 | 3 0.03 83.74 59 | 3 0.03 83.77 60 | 5 0.05 83.82 61 | 3 0.03 83.85 62 | 1 0.01 83.86 63 | 1 0.01 83.87 65 | 5 0.05 83.92 66 | 2 0.02 83.94 67 | 1 0.01 83.95 68 | 1 0.01 83.96 99 | 1,604 16.04 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 3 Jan 2016