-59.31% is the change from 639 to 260
Calculation steps:
[( 260 - 639 ) ÷ 639] x 100 = -59.31%
Formula
Percentage change = [(260 - 639) / 639] x 100
Subtract the new number by the original number
260 - 639 = -379
-379 ÷ 639 = -0.593114241001565
-0.593114241001565 x 100 = -59.31%