The IEA looks like an authoritative source. Agencies such as this one
and the DoE EIA get their data from industry sources. I trust them. It
is in industry's best interest to tell the truth. That's a problem in
the Middle East and Russia, but enough U.S. and European experts have
been to these oil fields to make reliable evaluations.
This is nothing to panic about. The worst case decline (the gray line)
is slow, giving plenty of time to develop other source of energy and
things like hybrid cars.
- Jed