Remove the unit areas from the AFRICA data set. DATA= specifies the input map data set and OUT= specifies the output map data set. The input map data set has a variable called REGION that is used as the BY-variable to identify the new unit areas. The ID statement specifies the current unit areas from the input map data set.

proc gremove data=newaf out=africa;
   by region;
   id id;
run;