Auto insurance is obviously different depending on the type of coverage you buy, but since the national average expenditure for car insurance is $795 a year and PA's average is $820, it can easily be inferred that Pennsylvanians are likely to pay a bit more on average for just about any type of coverage.
To answer that question, airfare shopping engine CheapAir.com monitored fares for more than 4 million flights in 2013 over a booking period ranging from 320 days in advance to one day in advance. Its researchers found that fares for domestic flights were lowest 54 days in advance.
While advance purchase does allow a greater selection and the possibility of better prices, booking too far in advance could yield higher prices. Most travel experts agree that one to three months in advance is really the soonest you should purchase airline tickets.