Microsoft Excel, like most spreadsheets, has a really convenient feature. When you copy any given cell into another cell, Excel will automatically adjust the formula references to other cells so refer to cells in the same relative position.
First, a look at Relative Addressing
In the example below, I copied thte formula in cell C2 into cells C3 through C8.
Excel automatically adjusted the formulas so that each formula referenced cells in the corresponding locations (columns a and b — it changed the row numbers) to the cells referenced by the cell that I was copying.
Continue reading HOWTO: Using Excel - How To Use Absolute Addressing