All the formulas are adjusted for you automatically so the same cells are always referred to.
If you try to insert more rows or columns are you receive the message "Cannot shift nonblank cells off the worksheet" there is data in either the very last column or the very last row or there are not enough empty rows or columns to be able to insert them all.
Another quick way to insert a row is to use the menu shortcut keys. (Alt + I , C) to insert a column and (Alt + I , R) to insert a row.
A quick way to display the (Edit > Delete Cells) dialog box is to press (Alt + E, D).
It is possible to insert just a range of cells instead of a whole column or row. For more details please refer to section Cells & Ranges.