That's according to NJ Transit records reviewed by the Wall Street Journal for the first six months of 2012.
The system's worst offenders are the 161 bus to Paterson and the 193 express to Wayne. One in four buses on the two lines left late.
Twelve percent - one in 10 buses - left the terminal more than five minutes late. But commuters say they sometimes wait up to an hour for a bus with a seat.
NJ Transit said it's running out of space at the terminal.
The Port Authority says it anticipates bus departures and arrivals from the terminal to grow by up to 34 percent in the next 25 years.
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