-75.43% is the change from 639 to 157
Calculation steps:
[( 157 - 639 ) ÷ 639] x 100 = -75.43%
Formula
Percentage change = [(157 - 639) / 639] x 100
Subtract the new number by the original number
157 - 639 = -482
-482 ÷ 639 = -0.7543035993740219
-0.7543035993740219 x 100 = -75.43%