-21.51% is the change from 688 to 540
Calculation steps:
[( 540 - 688 ) ÷ 688] x 100 = -21.51%
Formula
Percentage change = [(540 - 688) / 688] x 100
Subtract the new number by the original number
540 - 688 = -148
-148 ÷ 688 = -0.21511627906976744
-0.21511627906976744 x 100 = -21.51%