WTRG Economics provides a neat graph of real oil prices from 1869 to 2006 – all expressed in terms of 2006 prices:
Since 1869 US crude oil prices adjusted for inflation have averaged $21.05 per barrel in 2006 dollars compared to $21.66 for world oil prices.
Evan Davis says that current oil prices are not quite a historical record:
It’s clear that $100 a barrel is very high. Although it’s worth saying, it’s still not a record. 1864 was in fact the most expensive year for oil. It was over $104 in today’s money. Notwithstanding that record (and most of us in the media will ignore it when talking of record highs in the next few weeks – we’ll be using the high of $104.7 reached in 1980 after the Iranian revolution) we can at least say an impending $100 barrel is getting historically significant.
I suspect WTRG is using the GDP deflator, while Evan Davis is using CPI. Over at EconoSpeak, I asked the question about which deflator folks were using back on October 28. I guess we need to turn up the microphone over there as folks aren’t listening.