INDEX(...MATCH(IF...))) Function trouble

Hi guys,

Go easy on me please, I'm trying to get the hang of Index array functions but I'll freely admit I don't know what I'm doing.

Trying to extract the top 10 best/worst performing teams in terms of completion of various training course; 433 teams spread across 3 "Groups".

I've attached a sample of what I'm doing (any identifiable info has been removed leaving the rather unimaginative team names of "team 1, team 2 etc...),

So what I need to do is extract the lowest 10 performers from group A in terms of percentage completion of course 1, then do the same for group B and group C.

The Index function I've cobbbled together so far from various sites (this one was particularly helpful) doesn't seem to work, but I can't work out why:

{=INDEX($A$21:$A$454,MATCH_
(SMALL(IF($B$21:$B$454=$B$4,$C$21:$C$454),A6),_
$C$21:$C$454,0))}

I'm putting the index function in cell B6, and asking it to refer to range $A$6:$A$15 for the k-th value. Then I've got a simple vlookup in range C6:C15 to look up the actual percentage for the team returned in column B. There may be more eloquent ways of doing that but it works, if only the index function did.

All i'm getting is 10 identical results, all team 24 (or whatever the first row it finds with 0% seems to be, even if I sort the data different ways)

So, any ideas please? Not sure what the rules are with index arrays - does the data need sorting in any particular way etc... for this to work?

Or if anybody would be so good to suggest a completely different function/method of doing this, I'd be grateful (My point is to avoid having to pivot and paste values. I want to be able to populate range ("A21:G" & LR) with data and have the tables work it out automatically)

thanks