-87.99% is the change from 641 to 77
Calculation steps:
[( 77 - 641 ) ÷ 641] x 100 = -87.99%
Formula
Percentage change = [(77 - 641) / 641] x 100
Subtract the new number by the original number
77 - 641 = -564
-564 ÷ 641 = -0.8798751950078003
-0.8798751950078003 x 100 = -87.99%