To create a day-by-day look at the city’s traffic, officials crunched GPS information from nearly every yellow taxi trip taken in Manhattan’s business district — from 60th Street to the Battery — between November 2008 and October 2009.

In that 12-month period, weekday traffic in the district moved at an average of 9.5 miles per hour — about the speed of a farmyard chicken at full gallop.

Thursday, Nov. 13 was the slowest weekday of the year studied, with an average speed of 7.5 m.p.h. — about the speed of the typical jogger in Central Park. Excluding federal holidays, the fastest weekday: Monday, Sept. 28, at a speed of 11.7 m.p.h.

The four fastest days to drive in Manhattan, in order of average speed: New Year’s Day, Christmas, Memorial Day and July 4. (Thanksgiving Day? Hindered, presumably, by the Macy’s parade.)

On weekdays, speeds predictably peak between 5 and 6 in the morning (at a jaunty 16 m.p.h.), then decline sharply in the morning rush.

Not so predictably, speeds then stay low all day, even midday when commuters are at work. Traffic barely improves until the evening rush wanes about 7 p.m., hovering around 9 m.p.h. for much of the day.

Officials blame the midday congestion on a high level of commercial deliveries, which can clog side streets and stop up intersections. The data has helped officials as they consider raising daytime street parking rates to ease traffic tangles in Midtown.