Momentum strategy

[vonborge]

Dear Excel-forum,

Once again I'm into deep and look to you guys for help; I have a sheet with some 260.000+ observations and try to replicate the momentum strategy made famous by Jegadeesh and Titman in 1993:
I try to get find the 75 largest performers (based on their moving average for the previous three months) and then hold a portfolio of these stocks for the subsequent three months, i.e. get the geometric return of that period for the strategy.

If anyone has any ideas on how to do this efficiently I would be very thankful! I have attached an example over how I thought to build it up: momentum_example.xlsx

Many thanks in advance folks!

Best,
borge

[vonborge]

So I have managed to partly solve my problem with the following formula:
=IFERROR(IF(RANK('MA3'!ALT3;'MA3'!$B3:$ALT3;0)<=76;(((1+Returns!ALT8)*(1+Returns!ALT7)*(1+Returns!ALT6))^(1/3)-1);"");"")

However, for some months i get more than 75 stocks in my portfolio, is there a way to cap this to exactly 75?
The number is important as I have to have the same number of stocks in both my long and short portfolio for it to be a zero-investment portfolio.