-73.4% is the change from 966 to 257
Calculation steps:
[( 257 - 966 ) ÷ 966] x 100 = -73.4%
Formula
Percentage change = [(257 - 966) / 966] x 100
Subtract the new number by the original number
257 - 966 = -709
-709 ÷ 966 = -0.7339544513457557
-0.7339544513457557 x 100 = -73.4%