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

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        379        3.79        3.79
          1 |        429        4.29        8.08
          2 |        302        3.02       11.10
          3 |        184        1.84       12.94
          4 |        179        1.79       14.73
          5 |        240        2.40       17.13
          6 |        245        2.45       19.58
          7 |        286        2.86       22.44
          8 |        346        3.46       25.90
          9 |        298        2.98       28.88
         10 |        353        3.53       32.41
         11 |        390        3.90       36.31
         12 |        379        3.79       40.10
         13 |        459        4.59       44.69
         14 |        515        5.15       49.84
         15 |        611        6.11       55.95
         16 |        549        5.49       61.44
         17 |        565        5.65       67.09
         18 |        714        7.14       74.23
         19 |        560        5.60       79.83
         20 |        535        5.35       85.18
         21 |        559        5.59       90.77
         22 |        455        4.55       95.32
         23 |        450        4.50       99.82
         24 |          4        0.04       99.86
         99 |         14        0.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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