In 1925, the average price of gas was 10 cents a gallon.
The price of a gallon of gas in 1990 varied from $1.10 to $1.30
In 1925, gasoline cost 20 to 23 cents a gallon as evidenced by this photo: http://www.shorpy.com/node/3835?size=_original. Adjusted for inflation to 2009 dollars, that was $2.43 to $2.79 a gallon. As of 3/23/2009, the average price of gasoline on the East Coast, where this photo was taken, was $1.94 per gallon.
the average price per gallon of gas in 1988 was $1.08
The price per gallon of gasoline in 1914 was about $.17/gallon.
the average gas price for a gallon was $1.85 in the year of 1994.
In 2005, the average price per gallon of regular unleaded gas was $2.30
In 1997, the average price per gallon of regular unleaded gas was $1.23
About .20/Gallon
As of June 9, 2010, the average price of a gallon of regular gas in Missouri is $2.518
$ .99 cents a gallon
20 Cents a Gallon