Read Help for LOOKUP. The LOOKUP function assumes that column A is
sorted in ascending order, which is not true in your case. If you use
VLOOKUP, there is an optional final argument that can be used to request
exact matches with unsorted data.

Jerry

ab wrote:

Hi,

This is my spreadsheet. Column C has the LOOKUP formula.

A B C
53 a a LOOKUP(A2,$A$2:$A$14,$B$2:$B$14)
447 b b LOOKUP(A3,$A$2:$A$14,$B$2:$B$14)
1 020 c c |
1 906 d n |
2 007 e n |
1 876 f n |
1 707 g g |
1 549 h c |
1 411 i c |
1 292 j c |
1 190 k c |
1 102 m c |
1 026 n c |

The values in column C are supposed to be just the same as column B, but
they are not. There is something hidden going on here which i cannot
understand. I would appreciate any help.

Thanks.