-87.64% is the change from 647 to 80
Calculation steps:
[( 80 - 647 ) ÷ 647] x 100 = -87.64%
Formula
Percentage change = [(80 - 647) / 647] x 100
Subtract the new number by the original number
80 - 647 = -567
-567 ÷ 647 = -0.8763523956723338
-0.8763523956723338 x 100 = -87.64%