Working out the geomeans of varying lengths in the same column

Hey,
I'm trying to make a spread sheet that calculates the relevant 3M LIBOR rates for a bunch of possible investments. To do this I have to take a geomean of 3M LIBOR rates all the months for which I have return data on the investments. I have the relative row number for the beginning and end of the period I want the geomean of but I can't figure out how to write a formula.

so I have a column of rates and two cells displaying the rows I want:
___________ cell B2= 2, cell B3= 6
1.2
1.4
4.2
2.3
6.4
0.9
0.5

and I would like to work out the geomean of the number between (and including) rows 2 and 6. I tried to use:

=GEOMEAN(INDEX(A1:A7,B2,1):INDEX(A1:A7,B2,1))

But no avail.

Thanks


EDIT: I figured it out...