Bug? - Measure Area give perimeter result 1

[IfYouBuildIt]

UG NX 6.0.2.8

I'm attempting to use the Formula function for defining a rectangle's dimensions in a sketch. I'd like to size this rectangle such that it has the same area as another face in the same part. When I edit the dimension and select "Measure Area" in the formula editor, I can select the reference face fine, but it returns the perimeter of the face as opposed to the area. I swear I got this to work correctly just once. Any ideas about what I'm doing wrong or if this is a bug?

 

[cowski]

It returns the perimeter because it can't assign a length² expression to a length dimension.

As an alternative, create an associative face measurment feature before your sketch; dimension 1 leg of your rectangle as you like, and for the perpendicular leg enter an expression such as =p20/p22 where p20 is the expression representing the area of the face measure feature and p22 is the expression you entered for the length of the first leg of the rectangle.