Frequencies for first 10,000 rows of hour variable in person dataset :

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        302        3.02        3.02
          1 |        379        3.79        6.81
          2 |        260        2.60        9.41
          3 |        274        2.74       12.15
          4 |        239        2.39       14.54
          5 |        262        2.62       17.16
          6 |        301        3.01       20.17
          7 |        292        2.92       23.09
          8 |        308        3.08       26.17
          9 |        283        2.83       29.00
         10 |        332        3.32       32.32
         11 |        401        4.01       36.33
         12 |        455        4.55       40.88
         13 |        457        4.57       45.45
         14 |        545        5.45       50.90
         15 |        640        6.40       57.30
         16 |        502        5.02       62.32
         17 |        541        5.41       67.73
         18 |        648        6.48       74.21
         19 |        564        5.64       79.85
         20 |        573        5.73       85.58
         21 |        481        4.81       90.39
         22 |        397        3.97       94.36
         23 |        476        4.76       99.12
         24 |          5        0.05       99.17
         99 |         83        0.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016