-66.17% is the change from 399 to 135
Calculation steps:
[( 135 - 399 ) ÷ 399] x 100 = -66.17%
Formula
Percentage change = [(135 - 399) / 399] x 100
Subtract the new number by the original number
135 - 399 = -264
-264 ÷ 399 = -0.6616541353383458
-0.6616541353383458 x 100 = -66.17%