-52.27% is the change from 639 to 305
Calculation steps:
[( 305 - 639 ) ÷ 639] x 100 = -52.27%
Formula
Percentage change = [(305 - 639) / 639] x 100
Subtract the new number by the original number
305 - 639 = -334
-334 ÷ 639 = -0.5226917057902973
-0.5226917057902973 x 100 = -52.27%