I have numerous data collection points in one Excel sheet and would like to display them all in one column.

For example:
A1=3
A11=4
A21=5

I would like to use a forumla for the following cells to display the above:
B1=3
B2=4
B3=5

I know to use the "=" function but when i drag down the forumla it doesn't follow the pattern of every 10th cell.

Thanks,
Ollie