I'm trying to highlight cells in Column H where the value is the same 3 consecutive times e.g.

1. A
2. A
3. N
4. P
5. P
6. P
7. N
8. B
9. B

The 3 P's would be highlighted red but not the 2 A's or 2B's. whether this is doable in VBA or using a formula I don't know but I've been trying to get my head around it for a while. I'm sure its probably simple and I'm just stuck in a loop

any help would be muchly appreciated