wild_card,
If you put 1 or 2 in cell M$4, then the following formula for collum L computes the 1x or 2x results:
L75
=IF(N74="long",L74*(1+M$4*(E75/E74-1)),IF(N74="short",L74*(1-M$4*(E75/E74-1)),L74))
And =((L5122/10000)^0.05-1)*100 computes the 20 year compound annual return.
(edit: in the program sheet)
Arithmatic mean of annual returns is not very meaningful. For example, if year 1 has return of 100% and year 2 has -50%, the average of two is 25%. However, the actual total gain is actually 0%, which is dramatically different from 25%.
Jim