Do you mean AFTER the MA? According to phds.org, the shortest 20% of programs are MA and PhD in 6.1 years and below, next shortest 20% is 6.1-6.9 years, middle 20% is 6.9-7.7, next longest 20% is 7.7 to 8.5 years, and longest 20% is 8.5 years and above. Granted, I don't take phds.org to be the gospel truth, but I think this is pretty close to what we should be expecting.
For the record, UW Madison's median years required to complete a doctorate is 7.9, which means 20% of schools take even longer (according to phds.org). And from what I've heard, grad students who do quant work can get out of Madison quite a big quicker than qualitative people.