Phoenix Sky Harbor International Airport is offering discounted parking at its terminals during August. Throughout the month, a 40 percent-off coupon will be available at www.phxskyharbor.com. The full-day rate of $25 is reduced to $15 throughout the month. Airport officials say terminal parking often is underutilized in the summer, and since no local tax dollars are used to run the airport, a large portion of expenses are funded with parking revenue. As opposed to remote parking, terminal parking allows travelers to simply drive into the terminal, park, and walk directly to the gates. To get the coupon from www.phxskyharbor.com, travelers need to answer three questions on the airport's Web site. Economy parking continues to be available at $8 to $10 a day in the East and West lots and atop the Terminal 2 garage. The recession has cut into revenue at the airport as fewer people take vacations and businesses cut back on travel. Phoenix Sky Harbor International Airport saw 1.7 million fewer passengers in the first five months of this year compared with the same period in 2008. From January to May, 15.8 million passengers flew in and out of the Phoenix airport. That is down about 10 percent from 17.5 million for the same time frame in 2008, according to the Phoenix Aviation Department, which runs Sky Harbor.