Body Fat - don't trust the scale

Hola!

One of my friends at my home gym is a trainer, and back in April I asked her to measure my body fat %.  Using the calipers (pinchy thing).

Last weekend I decided it was time for a follow up, so I snagged her and asked her to measure me again.

This time the gym got a new "fancy" scale that claims it will tell you your body fat %.  So I hopped on the scale, and grabbed the handles.  It calculated my weight and then spit out my body fat %.  Before I tell you what it said, here's a generalized grid of where the percentages fall.

Women (this is an average indication, as many charts take age in to consideration)
Essential Fat  10-12%
Athletes  14-20%
Fitness  21-24%
Acceptable  25-31%
Obese  32%+
 
It said my body fat percentage was 31%.  Ummm, no.  Do you see how close that is to obese?
 
So we went to the caliper method.  I won't tell you exactly what it came out to, but let's just say it was a drastic difference.  The moral of the story being, don't trust a scale to tell you your body fat percentage because I am concrete proof that they can be very inaccurate.