I wish we could somehow develop a rig ‘efficiency’ chart.
Most people may not realize that all rigs are not the same.
During an oil boom, a lot of inefficient rigs are deployed which are the very first ones shut down during lower oil prices.
Really good rigs are never shut down.
The difference between one of these and an inefficient rig can be quite large, as good rigs can drill 2X as many wells as one that has a poor crew, management, or is prone to frequent shutdowns due to maintainence.
This is why a rig count cannot be indicative of the # of wells drilled, either in downturn or upturn.
Baker Hughes was producing a well count database but stopped.
http://phx.corporate-ir.net/phoenix.zhtml?c=79687&p=irol-wellcountus
The EIA Drilling Productivity Report, shows the increasing amount of oil produced per new well, but it also shows the increasing decline of older wells.
http://www.eia.gov/petroleum/drilling/pdf/dpr-full.pdf