Bonsoir,
augmentation de 5.3 % ⇒ coeff multiplicateur = 100/100 + 5.3/100 = 1.053
baisse de 1.6% ⇒ coeff. multiplicateur = (100/100 - 1.6/100) = 1 - 0.016 = 0.984
Taux d'évolution = ((1.053 * 0.984) - 1 )/100 = (1.03615 - 1) / 100 = 3.6 % arrondi
Bonne soirée