Could you do SUM(J17:J$17) ?
Alternatively, hide row 16 and make the formula =SUM(J16:J17)
Then when you insert at row 17 it will become = SUM(J16:J18)
Just have to make sure you have no data in row 16!
Alternatively, hide row 16 and make the formula =SUM(J16:J17)
Then when you insert at row 17 it will become = SUM(J16:J18)
Just have to make sure you have no data in row 16!