These survey results show that while most Americans haven't changed their vacation plans because of rising gas prices, a substantial proportion , 30%, have been compelled to alter vacation activities.

While two-thirds of American families say they haven't yet scaled back their summer vacations because of higher gas prices, the other one-third are significantly changing their travel plans, The Conference Board reports today in a special survey.

63 percent of families who are changing plans because of the run-up in gas prices say they will be staying closer to home. 26 percent say they have postponed or shortened their vacations this year, and about the same number say they are canceling vacation plans because of high gas prices. The survey covers 5,000 U.S. households and was conducted for The Conference Board by TNS in July, before news reports announced an alleged plot to blow up aircraft en route to the U.S. from London.

"These survey results show that while most Americans haven't changed their vacation plans because of rising gas prices, a substantial proportion -- one in three -- have been compelled to alter vacation activities."

When asked if higher gas prices have affected their commute to work, nearly one-fifth said yes. Among those who have changed their commuting routines, 20 percent said they are doing more work from home, another 16 percent said they are car-pooling, and 10 percent are using public transportation.