Frequencies for first 10,000 rows of plantype variable in planreport2006 dataset :

                            Plan Type |      Freq.     Percent        Cum.
--------------------------------------+-----------------------------------
                            1876 Cost |        640        6.40        6.40
 Continuing Care Retirement Community |          5        0.05        6.45
                              ESRD II |          2        0.02        6.47
                                  HMO |      1,917       19.17       25.64
                               HMOPOS |        186        1.86       27.50
                            Local PPO |        733        7.33       34.83
        MA Health Senior Care Options |         19        0.19       35.02
         MN Disability Health Options |          4        0.04       35.06
             MN Senior Health Options |        124        1.24       36.30
      Medicare Prescription Drug Plan |        951        9.51       45.81
                        National Pace |         56        0.56       46.37
                                 PFFS |      1,890       18.90       65.27
                  PSO (State License) |         14        0.14       65.41
                         Regional PPO |      3,455       34.55       99.96
                                 SHMO |          4        0.04      100.00
--------------------------------------+-----------------------------------
                                Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 14 Apr 2016