Dear all, When I run the codes of fuzzydid help file,but I get an error.I don't know why.

Code:
     use turnout_dailies_1868-1928.dta,clear

   gen G1872=(fd_numdailies>0)-(fd_numdailies<0) if  (year==1872)&fd_numdailies!=.&sample==1

   sort cnty90 year

   replace G1872=G1872[_n+1] if cnty90==cnty90[_n+1]&year==1868

   fuzzydid pres_turnout G1872 year numdailies, did tc cic newcateg(0 1 2 45)   breps(200) cluster(cnty90)

  When only one G variable is specified by the user, that variable must either be equal to 0, 1, or be 
  missing. See section 4.2 of the paper in the Stata journal for more details on how to create the G 
  variables.
Best
Raymond