Gas prices increase when measured in dollars. If you measure in euros, pounds, swiss francs, yen, etc… they haven't
Oil was below $40 per bbl in 2003; $120 in 2008
Euro was between USD 1.1 to 1.2 in 2003; $1.6 in 2008
Obviously, US $ depreciation is only part of the story.
More interestingly, I think, at least part of $ devaluation is DUE to increase in trade deficits due to rise in oil prices. These two have been mutually reinforcing each other's instability – leading to a vicious cycle.
