The retail price of gas was about 20 cents a gallon from 1929 to 1946. Disposable income in the 1930s was about $400 to $500 per year, equaling about $6,000 in today’s dollars. That means 1,000 gallons of gas cost as much as almost 49 percent of disposable income in 1933. To reach those levels today, gas would have to sell for between $14 and $17 per gallon, according to University of Michigan economist Mark J. Perry.