Find the biggest 'downturn' in a column of positive and negative numbers

[Armstrong69]

Hello,

I have a long column of various numbers, positive and negative.
Is it possible to find out the value of the biggest overall loss in the column (i.e. the biggest downturn)?

5
4
-3
-5
2
-3
11
0
-8
50
-8
50

In the above example I would like a return value of 9 (the biggest downturn as seen in A3 to A6).
The column will always have an overall positive sum. I don't mind having an extra column of data if it makes things easier.
Hope that makes sense. I've attached an example sheet.

Any help would be much appreciated! Thanks.