More than 64 percent of U.S. adults plan on taking a vacation during the next six months, according to a quarterly report co-authored by MMGY Global and the U.S. Travel Association.

It’s the second year that the outlook has been this bright, the report said. The percentage of Americans planning to travel between May and October is up from 61 percent last April and 56 percent in April 2010.

“The April results come as welcome news for destinations and travel companies ahead of the summer and fall travel seasons,” said Roger Dow, president and CEO of the U.S. Travel Association. “We are seeing a renewed enthusiasm for travel among consumers and barring any dramatic events, we believe that domestic travel will remain on solid footing through the summer travel season.”

Business travel is expected to improve slightly in the next six months, compared to the same timeframe as last year, with 17 percent of U.S. adults planning at least one business trip between May and October, a typically slow period for such travel. An encouraging sign that general business activity in the U.S. is on the mend is that business travelers took an average of 6.3 trips in the past 12 months, the highest average number in the past five years.

“While a more substantial uptick in the overall index would signal an even more robust turnaround from the industry’s recent malaise, the results of the April survey clearly reveal that travelers have become more confident in their personal financial situation. The forthcoming summer travel season is therefore a wonderful time for travel service suppliers to capitalize on this growing optimism,” said Peter Yesawich, vice chairman of MMGY Global.