If you put this formula in K20 and drag it down to K28 ...
=IF($D20=$C$11+1,$J19,IF($D20>$C$11+1,$N19,0))
So it is checking if the age is the year after retirement and returning the closing balance from the preceding year in Col J, or if older than 54, the closing balance from the preceding year in Col N ... or for years up to and including retirement, returning a 0
=IF($D20=$C$11+1,$J19,IF($D20>$C$11+1,$N19,0))
So it is checking if the age is the year after retirement and returning the closing balance from the preceding year in Col J, or if older than 54, the closing balance from the preceding year in Col N ... or for years up to and including retirement, returning a 0