The price of gasoline has risen to a record high, or has it? It depends on how you determine the record, according to an economist at North Carolina State University. Mike Walden, Reynolds Distinguished Professor and Extension Economist in the College of Agriculture and Life Sciences at North Carolina State University, says it's incorrect to compare prices in different years without adjusting for differences in the purchasing power of the dollar.

Because of general inflation, the purchasing power of the dollar falls each year. This means dollars in the past bought more (had higher purchasing power) than dollars today.

When dollars are adjusted for their purchasing power, Walden says the recent high in gas prices occurred in 1981. In that year, gas prices were the equivalent of $2.48 per gallon in terms of the purchasing power of today's dollars. Therefore, gas prices would have to go above $2.48 a gallon to set a new record.

There's a second way to measure the relative cost of gas prices, according to Walden. This is to calculate the number of minutes the average person would have to work to earn enough to purchase a gallon of gasoline. Today, it takes the average worker minutes to earn enough to buy a gallon of gas. Again, the recent high record was 1981, when it took 18.1 minutes to earn enough to buy a gallon of gas. Today's gas prices would have to rise above $2.80 a gallon to set a new record based on this method of calculating the relative cost of gasoline.

Walden is quick to emphasize that none of these calculations and comparisons ease today's burden of high gas prices. But they do show it has been worse in the past.