In MS Excel, how to use a formula to account for a blank cell?

Question

Let's say I'm using IF formula for greater than/less than.
Here's my formula: =IF(A4B4, "N", IF(A4=B4, "Y")))
This works, However, the problem is, if there is no vaule in the cell, it automatically assumes it is less than the value in the B column. I would like it to have a different outcome if the cell is left blank. How can I go about this?

Answer 1

=IF(OR(ISBLANK(B1),ISBLANK(C1)),"NA",IF(B1>=C1,"Y","N"))

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=IF(OR(ISBLANK(B1)
,ISBLANK(C1)),"NA",
IF(B1>=C1,"Y","N"))