To get a full set of relative row numbers in a range, you can use an array formula based on the ROW function.
In the example shown, the array formula in B5:B11 is:
On the worksheet, this must be entered as multi-cell array formula using Control + Shift + Enter
This is a robust formula that will continue to generate relative numbers even when the range is moved.
How this formula works
The first ROW function generates an array of 7 numbers like this:
{5;6;7;8;9;10;11}
The second ROW function generates an array with just one item like this:
{5}
which is then subtracted from the first array to yield:
{0;1;2;3;4;5;6}
Finally, 1 is added to get:
{1;2;3;4;5;6;7}
With a named range
You can adapt this formula to use with a named range. For example, in the above example, if you created a named range “data” for B5:D11, you can use this formula to generate row numbers:
In other array formulas
You’ll encounter this formula often in other array formulas that process data row-by-row.