-20.23% is the change from 771 to 615
Calculation steps:
[( 615 - 771 ) ÷ 771] x 100 = -20.23%
Formula
Percentage change = [(615 - 771) / 771] x 100
Subtract the new number by the original number
615 - 771 = -156
-156 ÷ 771 = -0.20233463035019456
-0.20233463035019456 x 100 = -20.23%