Hello forum

In column A a have a set of numbers which varies from time to time. These numbers must be substracted from the previous ones.

So if Range("A1:A12") the substractions must be

A2-A1
A3-A2
A4-A3
A5-A4 and so on.

Substructions must start from the next not used cell in the same Column

Since the range varies does anyone have an idea how to put all this in a code

Thank you