-71.02% is the change from 866 to 251
Calculation steps:
[( 251 - 866 ) ÷ 866] x 100 = -71.02%
Formula
Percentage change = [(251 - 866) / 866] x 100
Subtract the new number by the original number
251 - 866 = -615
-615 ÷ 866 = -0.710161662817552
-0.710161662817552 x 100 = -71.02%