I am trying to determine the appropriate equation for my application

I have the following:

=IF($D2="C-D",RANK($F2,(IF($D$2:$D$106="C-D",IF(ISNUMBER($F$2:$F$106),$F$2:$F$106))),0),NA() )

What I want to do is Rank the values in F2:F106 if the values in D2:D106 =
"C-D". I have committed this with CTRL SHIFT ENTER.

I get NA in the right places, and a VALUE error if the value in D2:D106 =
"C-D".

Thanks.

Barb Reinhardt