-75.9% is the change from 639 to 154
Calculation steps:
[( 154 - 639 ) ÷ 639] x 100 = -75.9%
Formula
Percentage change = [(154 - 639) / 639] x 100
Subtract the new number by the original number
154 - 639 = -485
-485 ÷ 639 = -0.758998435054773
-0.758998435054773 x 100 = -75.9%