retrospectively
adv. manner B2 Upper Intermediate US //ˌɹɛtɹoʊˈspɛktɪvɫi// UK //ɹˌɛtɹəʊspˈɛktɪvli// ret·ro·spec·tive·ly
adv. thinking about something after it has already happened. You use this when you look back on a past event to understand it better.
adv. considering or reviewing something in the light of past events. Often used to describe the act of applying a new rule or law to a previous period.
In retrospect, I wish I had taken that job offer.
The company decided to apply the new safety regulations retrospectively to all previous projects.
While the policy seemed justified at the time, a retrospective analysis of the data reveals several unintended consequences that the original committee had failed to anticipate.