INDEX, MATCH and LARGE formula

Hello

I am having difficulty with the Index and match function.

I have a spreadsheet where I have built a userform and the data from the user form is sent to a 'Data Store' tab.

From the 'Decision Overview' tab I would like to summarise the data that is sent to the ' Data Store' tab. The relevent data in that tab is the decision number in column A and the Policy Detail in column K. The overview tab will just have the name of the policy detail such as 'Investigation Objectives'.

As data is sent to the data store a number of decision numbers will be related to the detail 'Investigation Objectives'. For example, decision numbers 1,5,17,35 etc will be tagged as 'Investigation Objectives' in the data store.

I would like a formula that will look down column K and match 'Investigation objectives' (preferably by pointing to a cell on the overview sheet not by the text "Investigation objectives"), it will then go down column A and find the decision numbers. But I would like the numbers to be in ascending order so it will have to to find the largest / smallest and work back from there.

The data in the data store is unsorted but I can build a macro into the userform to sort this if needed.

I have used the Index and match function (B9 is the cell reference for "Investigation objectives")

=INDEX('Data Store'!$A:$A,MATCH($B9,'Data Store'!$K:$K,0))

and it works but I need to retrieve a range of numbers that match B9 and not just the one. I think the large or small function might be needed but I cant seem to get it to work.

Any help much appreciated. I have tagged this as urgent as I have a deadline to meet.

Thanks in advance

Gareth.