-0.5% is the change from 996 to 991
Calculation steps:
[( 991 - 996 ) ÷ 996] x 100 = -0.5%
Formula
Percentage change = [(991 - 996) / 996] x 100
Subtract the new number by the original number
991 - 996 = -5
-5 ÷ 996 = -0.0050200803212851405
-0.0050200803212851405 x 100 = -0.5%