With the recent gains, the price of oil is closing in on the inflation-adjusted highs hit in early 1980. Depending on the adjustment, a $38 barrel of oil in 1980 would be worth $96 to $101 or more today.
Should we inflation adjust using the GDP deflator or the CPI deflator?
James Hamilton does the latter in a chart entitled dollar price of West Intermediate divide by ratio of CPI. By this measure, we are not yet an inflation adjusted record. WRTG Economics has their own historical price in real terms though 2006. The inflation-adjusted real price record in terms of 2006 dollars was less than $70 per barrel. I suspect WRTG Economics is using the GDP deflator, which has not risen as much as the CPI deflator since 1980. AP was not kidding when they said “depending on the adjustment”. I get the $101 figure if we use CPI but where does the $96 dollar figure come from? The GDP deflator in 2007QIII were only 2.29 times the GDP deflator as of 1980QI so wouldn't the inflation-adjusted oil price been $87 not $96 dollars?
Of course, it also matters which measure of the spot rate one uses for this. WRTG also reports both the WTI spot price and Brent Spot price, which was considerably lower.