What's the usual length of a campaign?

[Hello]

How many sessions?

How long are these sessions?

How often do the players attend?

Are the sessions constant or do they go on hiatus?

[Dogstar]

Campaigns and players are so varied that without extensive research it would be nigh on impossible to answer this question so you can only get anecdotal answers on a forum.

It's akin to asking 'how long is a piece of string'