-35.26% is the change from 397 to 257
Calculation steps:
[( 257 - 397 ) ÷ 397] x 100 = -35.26%
Formula
Percentage change = [(257 - 397) / 397] x 100
Subtract the new number by the original number
257 - 397 = -140
-140 ÷ 397 = -0.3526448362720403
-0.3526448362720403 x 100 = -35.26%