lot depend on your definition of success. 5-1 return or more on investment for operator or just pay out break-even or gas production of simply paying quantity ( which most would say dry hole and plug it) vs dry hole.
Peter, essentially all shale gas wells are completed and produced unless they encounter a mechanical problem during drilling or frac'ing operations. This is not to say all are economic successes.
Jack Blake has wild questions:
How many HS wells are currently producing in TX/LA?
What is the current gas volume produced daily from HS wells in TX/LA?
hhhhhhhhhmmmmmmmmmmmthunkjackblake
Jack, there have been 2183 permitted HS wells total with 1485 in LA & 698 in TX. In Louisiana there have been 1138 HS wells spudded. I do not have a producing well count.
For gas production see the following discussion with charts thru March.