http://www.nytimes.com/2006/03/26/nyregion/26commute.html?_r=1&oref=login
Expanding Workday Makes Its Mark on Transit
By PATRICK McGEEHAN
Published: March 26, 2006
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The peaks of the commuter traffic known to some transit officials as "human high tides" still occur just before 9 a.m. and just after 5 p.m., but more and more commuters are straying from the herd. And the shift extends beyond New York. On Chicago's Metra train service, the fastest growth in ridership last year came on trains arriving between 6:30 and 7 a.m. at Union Station in downtown and those departing between 6 and 6:45 p.m., said Tom Miller, a Metra spokesman.