-84.09% is the change from 641 to 102
Calculation steps:
[( 102 - 641 ) ÷ 641] x 100 = -84.09%
Formula
Percentage change = [(102 - 641) / 641] x 100
Subtract the new number by the original number
102 - 641 = -539
-539 ÷ 641 = -0.8408736349453978
-0.8408736349453978 x 100 = -84.09%