average if array problems

Hello,

Having a problem understanding why the following formuale seems to return an incorrect answer

=AVERAGEIF(W9:W786:AS770:AS786,">"&PERCENTILE(W9:W786:AS770:AS786,95%))

basically i am looking at the average inside the 95%-100% percentile of a data set. As you can tell, the range of the data set is non continous in the same column, some of the data is in column W, some is in column AS. Please note I have pressed ctrl shift and enter when inputting the formulae.

This will return a different answer if I am to copy and paste the data currently labelled as AS770:786 underneath W9:W786 and input the formula:

=AVERAGEIF(W9:W802,">"&PERCENTILE(W9:w802,95%))

Anybody know it doesnt seem to work on a non continous range?

Many thanks

Indy