Anyone good with IF statements in Excel? I'm working on a project at work and I can't seem to get it right.

Here's my original statement.
=IF((B7/$B$2)*$B$1<1000,1000,(B7/$B$2*$B$1))

The If statement I wrote is correct and brings back the right values. But when I copy the formula down it automatically populates the cells with 1,000. I don't want it to populate anything until I actually key in a number in the adjacent cell. Does that make any sense??

It needs to say something like, if there is nothing in B7 then NULL or "", whatever.

Do I need to add AND, OR??