-88.01% is the change from 642 to 77
Calculation steps:
[( 77 - 642 ) ÷ 642] x 100 = -88.01%
Formula
Percentage change = [(77 - 642) / 642] x 100
Subtract the new number by the original number
77 - 642 = -565
-565 ÷ 642 = -0.8800623052959502
-0.8800623052959502 x 100 = -88.01%