25% is the change from 680 to 850
Calculation steps:
[( 850 - 680 ) ÷ 680] x 100 = 25%
Formula
Percentage change = [(850 - 680) / 680] x 100
Subtract the new number by the original number
850 - 680 = 170
170 ÷ 680 = 0.25
0.25 x 100 = 25%
Example