Translate the following English sentence to French:
"Aside from a few technical explanations relating to details, such as the exact number of ECB staff, there is only one valid reason that can be cited: the euro-optimism surrounding the launch of the euro, as it was called at the time, led people to believe that the single currency would naturally be strong and that the question of reserves was, therefore, secondary."
En dehors de quelques explications techniques de détail, comme le nombre exact d'agents de la BCE, on ne trouve qu'une seule raison valable : l'europtimisme entourant le lancement de l'euro, selon l'expression qui prévalait alors, conduisait à penser que la monnaie unique serait naturellement forte et que la question des réserves était donc secondaire.