-3.38% is the change from 503 to 486
Calculation steps:
[( 486 - 503 ) ÷ 503] x 100 = -3.38%
Formula
Percentage change = [(486 - 503) / 503] x 100
Subtract the new number by the original number
486 - 503 = -17
-17 ÷ 503 = -0.033797216699801194
-0.033797216699801194 x 100 = -3.38%