-17.55% is the change from 621 to 512
Calculation steps:
[( 512 - 621 ) ÷ 621] x 100 = -17.55%
Formula
Percentage change = [(512 - 621) / 621] x 100
Subtract the new number by the original number
512 - 621 = -109
-109 ÷ 621 = -0.17552334943639292
-0.17552334943639292 x 100 = -17.55%