Proof of Lack of Bikes, Courtesy of Oliver O'Brien

Oliver O'Brien, whose maps and analyses of bike share programs around the world are an invaluable resource, reports on the lack of bikes south of Central Park.

The area near Central Park seems to often end up with empty docking stations, caused perhaps by tourists starting their journeys here, going around Central Park and then downtown. 

and illustrates it here:

green = empty <10% of the time
yellow = 10-15%
red = 15-20%
red pins = empty 20%+ of the time