Can I update on my calendar the real duration of a meeting VS planned one?

Hi, 
I find myself in need to register on my calendar the real time I spend on meetings (organised by me or other collegues/clients) seen the fact that they last, most of the time, longer than previewed. 

I am looking for a way to update the duration of each given meeting, possibly only on my calendar without having to update the timeframe (when it is me creating the event) which activate a need for a response from the other partecipant or (when it is other parties creating the event) that would result into the proposition of a new time. In both cases, the meeting is already over. 
Thank you for any suggestion you might provide me on this regard. 
Best regards, 

Ilaria RICCI