select
        date_part('month', a."RPT_DATE") as month,
        date_part('year', a."RPT_DATE") as year,
        COUNT(*) as the_count
from "F501_502_CD" a
join "FILER_FILINGS_CD" b
on a."FILING_ID" =  b."FILING_ID"
where a."YR_OF_ELEC" = 2016
and a."FORM_TYPE" = 'F501'
group by 1, 2
order by 2, 1;