Frequencies for first 10,000 rows of mgntc_rsnc_img_srvc_cd variable in pos2010 dataset :

       SRV: |
   MAGNETIC |
  RESONANCE |
    IMAGING |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,626       86.26       86.26
          0 |      1,095       10.95       97.21
          1 |        145        1.45       98.66
          2 |        112        1.12       99.78
          3 |         22        0.22      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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