How can I calculate a trimmed average by using percentile ranks?

I would like to eliminate the top and bottom 5% of my data in order to get a more accurate average.

For example, if I have: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 in my data I want to exclude the top and bottom 5% meaning I am left with: 2, 3, 4, 5, 6, 7, 8, 9

That means the average is 5.5

Is there an aggregate formula to perform this calculation?