-67.51% is the change from 831 to 270
Calculation steps:
[( 270 - 831 ) ÷ 831] x 100 = -67.51%
Formula
Percentage change = [(270 - 831) / 831] x 100
Subtract the new number by the original number
270 - 831 = -561
-561 ÷ 831 = -0.6750902527075813
-0.6750902527075813 x 100 = -67.51%