You can make statistics say anything you want

Why it's important to distinguish between percentage and percentage points.

Pet peeve: “Reduces undesirable effects by 150%!” If you reduce something by 100%, you completely eliminate it. “Decrease failures by 200%.” How can you get rid of more than 100% of something? What they MEAN is that the old number is 150% or 200% higher than the improved number, it that’s not what is actually said.