-20.09% is the change from 642 to 513
Calculation steps:
[( 513 - 642 ) ÷ 642] x 100 = -20.09%
Formula
Percentage change = [(513 - 642) / 642] x 100
Subtract the new number by the original number
513 - 642 = -129
-129 ÷ 642 = -0.20093457943925233
-0.20093457943925233 x 100 = -20.09%