(Solved) sum maximum consecutive 1 value in a calendar row

Hi,

I've created a calendar that puts a value of 1 if an employee has leave on that day. If they don't, it has a value of 0 in that day. I'm trying to find a formula that will return the maximum sum of consecutive 1's in that calendar row for the employee. For example, over a two year period, I want to return the highest continuos period on leave for that period.

Regards
Wen