I'm trying to find the inverse rank within categories using an ArrayFormula. Let's suppose a sheet containing

```
A    B         C
----------     -----
1    0.14      2
1    0.26      3
1    0.12      1
2    0.62      2
2    0.43      1
2    0.99      3

```

Columns A:B are input data, with an unknown number of useful rows filled-in manually. A is the classifier categories, B is the actual measurements.

Column C is the inverse ranking of B values, grouped by A. This can be computed for a single cell, and copied to the rest, with e.g.:

```
=1+COUNTIFS($B$2:$B,"<" & $B2, $A$2:$A, "=" & $A2)

```

However, if I try to use ArrayFormula:

```
=ARRAYFORMULA(1+COUNTIFS($B$2:$B,"<" & $B2:$B, $A$2:$A, "=" & $A2:$A))

```

It only computes one row, instead of filling all the data range.

A solution using COUNT(FILTER(...)) instead of COUNTIFS fails likewise.

I want to avoid copy/pasting the formula since the rows may grow in the future and forgetting to copy again could cause obscure miscalculations. Hence I would be glad for help with a solution using ArrayFormula.

Thanks.