Frequencies for first 10,000 rows of dgestat variable in natl1977 dataset : Gestation | Freq. Percent Cum. ------------+----------------------------------- 17 | 4 0.04 0.04 18 | 2 0.02 0.06 20 | 3 0.03 0.09 21 | 3 0.03 0.12 22 | 2 0.02 0.14 23 | 2 0.02 0.16 24 | 4 0.04 0.20 25 | 10 0.10 0.30 26 | 10 0.10 0.40 27 | 13 0.13 0.53 28 | 16 0.16 0.69 29 | 28 0.28 0.97 30 | 27 0.27 1.24 31 | 36 0.36 1.60 32 | 54 0.54 2.14 33 | 81 0.81 2.95 34 | 127 1.27 4.22 35 | 171 1.71 5.93 36 | 274 2.74 8.67 37 | 491 4.91 13.58 38 | 861 8.61 22.19 39 | 1,551 15.51 37.70 40 | 1,756 17.56 55.26 41 | 1,242 12.42 67.68 42 | 664 6.64 74.32 43 | 338 3.38 77.70 44 | 161 1.61 79.31 45 | 102 1.02 80.33 46 | 51 0.51 80.84 47 | 31 0.31 81.15 48 | 21 0.21 81.36 49 | 12 0.12 81.48 50 | 10 0.10 81.58 51 | 5 0.05 81.63 52 | 10 0.10 81.73 99 | 1,827 18.27 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 3 Jan 2016