-19.66% is the change from 646 to 519
Calculation steps:
[( 519 - 646 ) ÷ 646] x 100 = -19.66%
Formula
Percentage change = [(519 - 646) / 646] x 100
Subtract the new number by the original number
519 - 646 = -127
-127 ÷ 646 = -0.19659442724458204
-0.19659442724458204 x 100 = -19.66%