(SQL1: Essential course note PDF, p237 and p245 s104s10)
I think the newly created column name should be "EstSum", not "EstPct", because it is the sum of the estimated population of the countries, not a percent (see below).



The code and results are as follows:
proc sql;
select * from sq.globalfull(obs=1);
quit;
proc sql outobs=3;
select distinct countrycode,
estyear1pop
from sq.globalfull;
quit;
proc sql;
select sum(estyear1pop) format comma20.
from (select distinct countrycode,
estyear1pop
from sq.globalfull);
quit;
