287.94% is the change from 257 to 997
Calculation steps:
[( 997 - 257 ) ÷ 257] x 100 = 287.94%
Formula
Percentage change = [(997 - 257) / 257] x 100
Subtract the new number by the original number
997 - 257 = 740
740 ÷ 257 = 2.8793774319066148
2.8793774319066148 x 100 = 287.94%