-58.59% is the change from 821 to 340
Calculation steps:
[( 340 - 821 ) ÷ 821] x 100 = -58.59%
Formula
Percentage change = [(340 - 821) / 821] x 100
Subtract the new number by the original number
340 - 821 = -481
-481 ÷ 821 = -0.5858708891595615
-0.5858708891595615 x 100 = -58.59%