Thanks Brenner. That doesn't work as count(total Recordnumber) sums the values for all the records in the table and not just by each year (column).
However, I obtained the answer on twitter from @countnazgul:
"use aggr(NoDistinct sum( ... to have the total number in all rows"
The reason for using NoDistict as per @countnazgul is that "aggr return only 1 num - total for whole year.nodistinct spreads this num across all rows.distinct is ON by default for aggr"
Hope this helps others out there.