-47.45% is the change from 647 to 340
Calculation steps:
[( 340 - 647 ) ÷ 647] x 100 = -47.45%
Formula
Percentage change = [(340 - 647) / 647] x 100
Subtract the new number by the original number
340 - 647 = -307
-307 ÷ 647 = -0.47449768160741884
-0.47449768160741884 x 100 = -47.45%