Formulas can typically be copied down. For example, if you have in C1
the following formula:

=A1*B1

then you can copy it down and the cell references will change. For
example, in C5, it will automatically become

=A5*B5

If such is the nature of your formula, then you can fearlessly insert
rows and then simply copy the existing formulas along the entire
column.

HTH
Kostis Vezerides