-2.84% is the change from 633 to 615
Calculation steps:
[( 615 - 633 ) ÷ 633] x 100 = -2.84%
Formula
Percentage change = [(615 - 633) / 633] x 100
Subtract the new number by the original number
615 - 633 = -18
-18 ÷ 633 = -0.02843601895734597
-0.02843601895734597 x 100 = -2.84%