-63.05% is the change from 839 to 310
Calculation steps:
[( 310 - 839 ) ÷ 839] x 100 = -63.05%
Formula
Percentage change = [(310 - 839) / 839] x 100
Subtract the new number by the original number
310 - 839 = -529
-529 ÷ 839 = -0.6305125148986889
-0.6305125148986889 x 100 = -63.05%