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

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        351        3.51        3.51
          1 |        376        3.76        7.27
          2 |        408        4.08       11.35
          3 |        252        2.52       13.87
          4 |        223        2.23       16.10
          5 |        276        2.76       18.86
          6 |        345        3.45       22.31
          7 |        281        2.81       25.12
          8 |        288        2.88       28.00
          9 |        318        3.18       31.18
         10 |        283        2.83       34.01
         11 |        405        4.05       38.06
         12 |        443        4.43       42.49
         13 |        381        3.81       46.30
         14 |        492        4.92       51.22
         15 |        610        6.10       57.32
         16 |        470        4.70       62.02
         17 |        606        6.06       68.08
         18 |        637        6.37       74.45
         19 |        484        4.84       79.29
         20 |        569        5.69       84.98
         21 |        564        5.64       90.62
         22 |        430        4.30       94.92
         23 |        425        4.25       99.17
         24 |          1        0.01       99.18
         99 |         82        0.82      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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