Start New Sum When Certain Criteria Is Met

You wouldn't need to recover a stake that wasn't lost so if C50 was =1 then N50 stake was fine. The sum would start from N51. I only divide by the most recent Odds_Numeric as that is the odds on offer for the forthcoming event. All other Odds_Numeric data is redundant as soon as the result is in.

So if the sum of 10 losers in a row is £10 and the next bet is priced at 5/1 (displayed as 5 in the column as it doesn't include the stake) your recovery would be 10/5 = £2 for the recovery plus your current stake as shown in the corresponding column F.