-0.8% is the change from 251 to 249
Calculation steps:
[( 249 - 251 ) ÷ 251] x 100 = -0.8%
Formula
Percentage change = [(249 - 251) / 251] x 100
Subtract the new number by the original number
249 - 251 = -2
-2 ÷ 251 = -0.00796812749003984
-0.00796812749003984 x 100 = -0.8%