-63.99% is the change from 858 to 309
Calculation steps:
[( 309 - 858 ) ÷ 858] x 100 = -63.99%
Formula
Percentage change = [(309 - 858) / 858] x 100
Subtract the new number by the original number
309 - 858 = -549
-549 ÷ 858 = -0.6398601398601399
-0.6398601398601399 x 100 = -63.99%