-40.07% is the change from 851 to 510
Calculation steps:
[( 510 - 851 ) ÷ 851] x 100 = -40.07%
Formula
Percentage change = [(510 - 851) / 851] x 100
Subtract the new number by the original number
510 - 851 = -341
-341 ÷ 851 = -0.4007050528789659
-0.4007050528789659 x 100 = -40.07%