NEW YORK (CBSNewYork) — Newark Liberty Airport tops a new ranking of the nation’s airports with the worst on-time performance during the summer travel months.

The internet travel site MileCards.com went through 10 years of data and found 66.5 percent of flights arriving at Newark were on time from June to August over the past decade. That’s the lowest score among the country’s 50 busiest airports.

LaGuardia Airport was a close second with a 66.9 percent on-time arrival rate, followed by San Francisco International, John F. Kennedy Airport and Boston.

“New York area airports came at the bottom of the list consistently for that entire 10-year period,” MileCards.com Director Brian Karimzad said. “Summer is actually one of the worst times of the year to be flying when it comes to delays, in fact at Kennedy and LaGuardia you’ll have more delays in the summer than you’ll find during the dead of winter.”

The Port Authority of New York and New Jersey, which operates Newark, LaGuardia and Kennedy airports, said it has been working with the Federal Aviation Administration on putting in place “NextGen,” a new air traffic control system designed to reduce delays.

The rankings were based on arrivals, time spent taxiing and time waiting to get to a gate once a plane lands.

The airport with the best on-time performance was Kahului in Hawaii followed by Honolulu and Salt Lake City.