NEW YORK - An MTA document indicates that implementing the newly approved congestion pricing plan will be complicated.

The document reveals the cost of driving in Manhattan below 61st St. could vary depending on different factors.

That includes how much traffic is on the street, how far you drive, and how much time you spend in the congestion zone.

New York's congestion pricing statute says the toll must vary by time of day but provides little detail about an exact pricing structure.

The MTA wants the option to have a more complicated system - one that would also let the agency toll trips that start and end inside the zone.

An exact pricing structure, as well as exemptions will be set by MTA officials with oversight from a six-member review board.

Those members have not yet been appointed.