-87.43% is the change from 509 to 64
Calculation steps:
[( 64 - 509 ) ÷ 509] x 100 = -87.43%
Formula
Percentage change = [(64 - 509) / 509] x 100
Subtract the new number by the original number
64 - 509 = -445
-445 ÷ 509 = -0.8742632612966601
-0.8742632612966601 x 100 = -87.43%