Tennessee, TN, June 21- Average retail gasoline prices in Tennessee have risen 3.7 cents per gallon in the past week, averaging $2.54/g yesterday. This compares with the national average that has increased 3.7 cents per gallon in the last week to $2.73/g, according to gasoline price website TennesseeGasPrices.com. Including the change in gas prices in Tennessee during the past week, prices yesterday were 1.7 cents per gallon higher than the same day one year ago and are 13.4 cents per gallon lower than a month ago. The national average has decreased 9.0 cents per gallon during the last month and stands 7.2 cents per gallon higher than this day a year ago. About TennesseeGasPrices.com GasBuddy.com operates over 200 live gasoline price-tracking websites, including TennesseeGasPrices.com. GasBuddy.com was named one of Time magazine's 50 best websites and to PC World's 100 most useful websites of 2008.