-48.78% is the change from 490 to 251
Calculation steps:
[( 251 - 490 ) ÷ 490] x 100 = -48.78%
Formula
Percentage change = [(251 - 490) / 490] x 100
Subtract the new number by the original number
251 - 490 = -239
-239 ÷ 490 = -0.48775510204081635
-0.48775510204081635 x 100 = -48.78%