Frequencies for first 10,000 rows of state_rgn_cd variable in pos2007 dataset :

      state |
region code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |         88        0.88        0.88
        001 |      3,938       39.38       40.26
         AZ |      1,123       11.23       51.49
        BAK |         97        0.97       52.46
        BER |        273        2.73       55.19
         BK |        289        2.89       58.08
        BK1 |         22        0.22       58.30
         FR |        275        2.75       61.05
         L1 |        384        3.84       64.89
         L2 |        284        2.84       67.73
         L3 |        164        1.64       69.37
         L4 |        281        2.81       72.18
         L5 |        257        2.57       74.75
         M2 |          2        0.02       74.77
        ORG |        186        1.86       76.63
        RIV |        124        1.24       77.87
        RWC |        218        2.18       80.05
         S1 |        353        3.53       83.58
         S2 |         14        0.14       83.72
         S3 |        208        2.08       85.80
         SA |         44        0.44       86.24
         SB |         38        0.38       86.62
         SD |        336        3.36       89.98
        SDS |         81        0.81       90.79
         SF |        188        1.88       92.67
         SJ |        227        2.27       94.94
         SR |         82        0.82       95.76
        TUC |        268        2.68       98.44
        VEN |        156        1.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017