Evaluate to columns; compare two columns and return result

Hi! Good afternoon

Thanks for all your support!

I use MS Office 2007

I have 2 columns : Amount and Rate

Amount RATE DESIRED
556583.53 NA NA
541388.85 NA NA
563172.72 NA NA
470147.84 0.32 150447.3088
557689.88 0.19 105961.0772
368929.92 0.32 118057.5744
669637.41 0.32 214283.9712
316508.91 0.32 101282.8512
318117.64 0.52 165421.1728
424263.52 NA NA
366445.48 NA NA
497342 NA NA
470445.58 0.19 89384.6602
379561.09 NA NA

I need column "C" to check whether B is 'NA' if true return 'NA'
ELSE calculate: a*B

I tried with a folmula :

=IF(C2="NA","NA","=A2*B2")

First part is ok : it is returning "NA"
but it does not multiply A*B if NA not found

Appreciate your early reply

Hi try this
=IF(B2="NA","NA",A2*B2)
Punnam