That's true, but livery cab drivers have lots of ways to influence that number. They can shrewdly choose a good spot to cruise. They can give their cellphone numbers to riders they've established a rapport with in order to win advance bookings. In small towns with just a few drivers - or in cities where drivers are in a co-op - they can spend some of their earnings to advertise the taxi company. Livery drivers can offer discounts to riders going a long way.
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