-28.79% is the change from 639 to 455
Calculation steps:
[( 455 - 639 ) ÷ 639] x 100 = -28.79%
Formula
Percentage change = [(455 - 639) / 639] x 100
Subtract the new number by the original number
455 - 639 = -184
-184 ÷ 639 = -0.28794992175273865
-0.28794992175273865 x 100 = -28.79%