Frequencies for first 10,000 rows of opq variable in nsrd dataset :

    Average |
 Opaque Sky |
      Cover |
   (tenths) |      Freq.     Percent        Cum.
------------+-----------------------------------
         .5 |          2        0.02        0.02
         .7 |          2        0.02        0.04
         .8 |          1        0.01        0.05
         .9 |          2        0.02        0.07
          1 |          1        0.01        0.08
        1.1 |          4        0.04        0.12
        1.2 |          1        0.01        0.13
        1.3 |          2        0.02        0.15
        1.4 |          4        0.04        0.19
        1.5 |          8        0.08        0.27
        1.6 |          5        0.05        0.32
        1.7 |          4        0.04        0.36
        1.8 |         10        0.10        0.46
        1.9 |         18        0.18        0.64
          2 |          8        0.08        0.72
        2.1 |         12        0.12        0.84
        2.2 |         14        0.14        0.98
        2.3 |         20        0.20        1.18
        2.4 |         18        0.18        1.36
        2.5 |         23        0.23        1.59
        2.6 |         22        0.22        1.81
        2.7 |         32        0.32        2.13
        2.8 |         38        0.38        2.51
        2.9 |         32        0.32        2.83
          3 |         41        0.41        3.24
        3.1 |         51        0.51        3.75
        3.2 |         56        0.56        4.31
        3.3 |         68        0.68        4.99
        3.4 |         57        0.57        5.56
        3.5 |         93        0.93        6.49
        3.6 |        100        1.00        7.49
        3.7 |         89        0.89        8.38
        3.8 |        102        1.02        9.40
        3.9 |        101        1.01       10.41
          4 |         97        0.97       11.38
        4.1 |        121        1.21       12.59
        4.2 |        123        1.23       13.82
        4.3 |        145        1.45       15.27
        4.4 |        143        1.43       16.70
        4.5 |        147        1.47       18.17
        4.6 |        157        1.57       19.74
        4.7 |        174        1.74       21.48
        4.8 |        209        2.09       23.57
        4.9 |        215        2.15       25.72
          5 |        216        2.16       27.88
        5.1 |        239        2.39       30.27
        5.2 |        236        2.36       32.63
        5.3 |        258        2.58       35.21
        5.4 |        260        2.60       37.81
        5.5 |        256        2.56       40.37
        5.6 |        240        2.40       42.77
        5.7 |        268        2.68       45.45
        5.8 |        289        2.89       48.34
        5.9 |        307        3.07       51.41
          6 |        244        2.44       53.85
        6.1 |        272        2.72       56.57
        6.2 |        274        2.74       59.31
        6.3 |        294        2.94       62.25
        6.4 |        280        2.80       65.05
        6.5 |        287        2.87       67.92
        6.6 |        274        2.74       70.66
        6.7 |        244        2.44       73.10
        6.8 |        266        2.66       75.76
        6.9 |        236        2.36       78.12
          7 |        221        2.21       80.33
        7.1 |        229        2.29       82.62
        7.2 |        200        2.00       84.62
        7.3 |        203        2.03       86.65
        7.4 |        183        1.83       88.48
        7.5 |        148        1.48       89.96
        7.6 |        159        1.59       91.55
        7.7 |        149        1.49       93.04
        7.8 |        121        1.21       94.25
        7.9 |         96        0.96       95.21
          8 |         72        0.72       95.93
        8.1 |         71        0.71       96.64
        8.2 |         64        0.64       97.28
        8.3 |         52        0.52       97.80
        8.4 |         40        0.40       98.20
        8.5 |         44        0.44       98.64
        8.6 |         25        0.25       98.89
        8.7 |         24        0.24       99.13
        8.8 |         18        0.18       99.31
        8.9 |         13        0.13       99.44
          9 |         23        0.23       99.67
        9.1 |         12        0.12       99.79
        9.2 |          9        0.09       99.88
        9.3 |          3        0.03       99.91
        9.4 |          3        0.03       99.94
        9.5 |          3        0.03       99.97
        9.6 |          1        0.01       99.98
        9.7 |          1        0.01       99.99
        9.8 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016