-47.9% is the change from 1000 to 521
Calculation steps:
[( 521 - 1000 ) ÷ 1000] x 100 = -47.9%
Formula
Percentage change = [(521 - 1000) / 1000] x 100
Subtract the new number by the original number
521 - 1000 = -479
-479 ÷ 1000 = -0.479
-0.479 x 100 = -47.9%