Conspiracies can last for varying lengths of time, from weeks to years, depending on the complexity of the plan and the ability of those involved to keep it secret. Some conspiracies have been uncovered quickly, while others have persisted for years before being exposed.
5 to 10 years
A Conspiracy of Paper has 448 pages.
The Olympic Conspiracy has 304 pages.
Conspiracy Encyclopedia has 320 pages.
A Conspiracy of Kings has 330 pages.
Conspiracy of Calaspia has 598 pages.
The Doomsday Conspiracy has 416 pages.
Grand Conspiracy has 624 pages.
The Red Wolf Conspiracy has 462 pages.
10 years
As the statutes differ from state-to-state there is no certain generallized answer to this question.If the conspiracy came to fruition, you could be charged as a principle in the offense, a felony. If the robbery never took place, possibly a misdemeanor.
There are hundreds or thousands of conspiracies.