-70.7% is the change from 877 to 257
Calculation steps:
[( 257 - 877 ) ÷ 877] x 100 = -70.7%
Formula
Percentage change = [(257 - 877) / 877] x 100
Subtract the new number by the original number
257 - 877 = -620
-620 ÷ 877 = -0.7069555302166477
-0.7069555302166477 x 100 = -70.7%