How long does it take you to finish a manga?

I'm curious about how much others are able to complete a manga through and through. Depending on how interesting the manga is to me usually determines my time, I don't read manga that often and honestly have not read that much to even call myself a manga reader but from my experiences, I've had to take several breaks but I think that's really just from my attention span.

depending on the size .it takes around 15-20 days for one manga

It depends on how long or if i have motivation, but usually a week or 2 per book.