-33.6% is the change from 1000 to 664
Calculation steps:
[( 664 - 1000 ) ÷ 1000] x 100 = -33.6%
Formula
Percentage change = [(664 - 1000) / 1000] x 100
Subtract the new number by the original number
664 - 1000 = -336
-336 ÷ 1000 = -0.336
-0.336 x 100 = -33.6%