-0.4% is the change from 991 to 987
Calculation steps:
[( 987 - 991 ) ÷ 991] x 100 = -0.4%
Formula
Percentage change = [(987 - 991) / 991] x 100
Subtract the new number by the original number
987 - 991 = -4
-4 ÷ 991 = -0.004036326942482341
-0.004036326942482341 x 100 = -0.4%