named ranged within named range

not even sure why you want that!
COUNTA($B$8:$B8) what do you think it does as a named formula?
at the moment = nth_occurrence in a cel dragged down
would be the same as COUNTA($B$8:$B8) filled down ie
=COUNTA($B$8:$B8)
=COUNTA($B$8:$B9)
=COUNTA($B$8:$B10)
=COUNTA($B$8:$B11)
=COUNTA($B$8:$B12)
=COUNTA($B$8:$B13)
=COUNTA($B$8:$B14)
=COUNTA($B$8:$B15)
=COUNTA($B$8:$B16)
=COUNTA($B$8:$B17)


but
=ROWS(INDIRECT("1:"&nth_occurrence)) would be the way to construct it