_dta:
  1.  by Jean Roth , jroth@nber.org , 20 Apr 2015

  obs:     4,474,292                          
 vars:             2                          20 Apr 2015 17:25
 size:    62,640,088                          (_dta has notes)
-------------------------------------------------------------------------------
              storage   display    value
variable name   type    format     label      variable label
-------------------------------------------------------------------------------
npi             str10   %10s                  National Provider Identifier
                                                (NPI)
penumdate       float   %td                   Provider Enumeration Date
-------------------------------------------------------------------------------
Sorted by:  npi