How to sum only if a value exists in column A and another in Column B.

[Anonymous]

Hi, 

I have a problem that is driving me nuts. Referring to the image attached, I want to calculate column V based on a conditional formula. If there is a value in column A AND column B then calculate value for column V. However, the basic IF statement is not working. Right now, you can see in the totals that column A sums up to 376 and column B sums to 10. The total % for column V (allocation) is 3755%, however, in reality it should only show 100%. 

I have achieved something using Summarize but I can not add dates in it so it gives me the total of all values in column A + column B respectively unable to filter by dates. 

Can anyone please help me?

[Greg_Deckler]

Should be something along the lines of:

IF(ISBLANK([ColumnA]) && ISBLANK([ColumnB]), true, false)

Spoiler