|First, a posting tip...|
When posting in a help forum, please try to use a subject line that is specific to the contents of your post.
If everyone used generic subject lines like "Need Excel Macro" or "Need Excel Help" (something we see a lot!) then we couldn't tell one question from another and things would get very confusing around here.
I fixed the subject line for this thread, but we'd appreciate it if you could keep that in mind for future posts.
That said, we need a little more information about the layout of your data. When you say a number is removed, what do you mean? How is the number removed? How does a number take it's place?
Typically a formula can update automatically when a number within a range changes, but since you asked for a macro, I have to assume that something else is going on in your spreadsheet.
Click Here Before Posting Data or VBA Code ---> How To Post Data or Code.