sum a range until the cell to the left is zero

[rwelch@fairfieldglad]

I want to get the years old column/cells
that would look to the left and calculate
the numbers of years an account is…

For example above, row 2 - should return
a 3, as the account is 3 years old

Row 3 needs to be a 1….
meaning stop counting going to the left
once a cell that is "0" is reached.
See attached file