Rarely before had a Port Authority bus looked so good.
Bundled up against the morning's chill of minus 7 degrees, David Schreib hustled into the warmth of the 61B bus on a frigid Tuesday in Edgewood last month. It was a good start to the day: Mr. Schreib, a financial systems analyst at Carnegie Mellon University, had to wait only a few minutes at the corner of South Braddock and Hutchinson avenues for his ride.
Most evenings? Different story. Helpless against Oakland's infamous rush-hour traffic, Mr. Schreib says he sometimes waits more than an hour for a bus to arrive.
He takes it with a shrug. After seven years of commuting through Pittsburgh's busiest transit corridor, he's pretty good at waiting.
"It's not even worth looking at the schedule," Mr. Schreib said.
While hour-long waits may be rare in Pittsburgh, late buses are not. New figures from the Port Authority of Allegheny County show that, on average, one of every five buses is late. The worst four routes in the system run late a third of the time.
With a bus considered "on time" if it arrives at a stop between two minutes before the scheduled time and up to five minutes after, 21.1 percent of trips lagged late and 10.8 percent ran early, resulting in an overall on-time rate of 68.1 percent.
The lateness figure jumps to more than 30 percent for the most tardy routes, especially those on the traffic-heavy gauntlet between Downtown, Oakland and Squirrel Hill.
Officials at the transit agency say their drivers can't control the traffic, the weather or the number of riders fumbling with cash. But with GPS units already tracking delays, and the Port Authority developing a system to deliver that information to riders' smartphones and computers in real time, the agency hopes riders like Mr. Schreib will soon have a more predictable ride -- if not always a quicker one.
"We're not entirely satisfied with those numbers," spokesman Jim Ritchie said of the on-time performance. "We'd like to improve the overall reliability of our system."
There is no national standard for on-time service, but many transit agencies have established goals. King County, Wash., which includes Seattle, strives to have 80 percent of trips arriving from 1 minute early to 5 minutes late, a goal it rarely met last year. Washington, D.C., strives for 78 percent on-time performance by buses, but fell well short of that based on an independent study. Atlanta's bus system has a goal of 76 percent on-time performance.
Port Authority has an "internal goal" of 90 percent on-time service, Mr. Ritchie said.
Errol D. Noel, professor and director of the transportation research center at Howard University in Washington, D.C., who did an extensive study of bus on-time performance there, said it is important for transit agencies to deliver what they promise. He said on-time performance -- which he defines as no more than one minute early or five minutes late -- should stay above 75 percent.
The Port Authority data include just more than 7 million weekday measurements, recorded from May to October of last year. GPS trackers plot each bus's progress along its route, comparing its running time to the printed schedule at various checkpoints.
Once aggregated, the data show the most reliable Port Authority routes tend to be those using the three buses-only corridors. Twenty-two of 26 routes on the East, West and South busways operated on time or early more than 80 percent of the time.
Also high in reliability were routes serving the North Side. Authority officials said that was likely due to the relatively short loop the buses travel Downtown, crossing the Allegheny River to a quick turnaround at Liberty Avenue.
Most routes coming from other directions travel farther into Downtown, putting them at greater risk of being delayed by traffic.
On the other hand, buses traveling through Oakland were most likely to be late. Four principal routes, the 61A and 61B and 71A and 71B, all were late more than 30 percent of the time. Seven of the 11 Port Authority routes with late rates of 30 percent or higher were Oakland routes.
In addition to heavy traffic in the corridor, the buses see a greater volume of passenger turnover as they make their way past the universities, meaning longer dwell times at bus stops, Mr. Ritchie said.
The worst route on the books? The P69, also known as the Trafford Flyer, which posted a 54 percent on-time record. (Port Authority officials say a detour during construction of the new Trafford Veterans Memorial Bridge temporarily flummoxed the schedule and sank on-time rates.)
On that Tuesday morning last month, the 61B mostly stuck to its schedule, flying down roads that normally would be clogged with traffic. (Cold-related cancellations at local schools might have eased congestion, bus riders ruminated.) But once the bus rounded Downtown and headed back toward Braddock, it started running early, hitting stops four minutes ahead of schedule.
The next bus idled for a few minutes outside Braddock's Carnegie Library to realign itself with the timetable.
Authority officials believe most late trips are caused by forces beyond the operator's control, including crashes, bad weather and congestion from rush-hour traffic or special events.
"Buses experience the same conditions on the road as people do driving in their cars," Mr. Ritchie said.
Mr. Noel agreed. Drivers "do have some leeway but not much in a dense urban area," he said. "The key is accurate scheduling."
Port Authority CEO Ellen McLean is counting on technology to chart better paths. Meaningful on-time data barely existed two years ago, when the transit company relied on bus-watchers armed with clipboards to keep track of how the routes were running.
They now have more information than they know what to do with. Each daily download of bus data takes about a week to process. About 25 million new records are generated a month.
Despite the overload, Ms. McLean says the Port Authority has already used the new data to rejigger routes for release in March, with additional modifications coming in September.
One area of change will be the Oakland routes, which will get more frequent trips from the end of the evening rush until 9 p.m.
"More changes will be made based on data," Ms. McLean said. "Before, I'd send someone out there to ride the bus -- and who knows what they were looking at?"
To be sure, Ms. McLean's massive database will not soon usher in a transit utopia, where buses fly, arrive on the dot and dispense hot cocoa to shivering passengers. Waiting, at least for now, will remain part of the package.
And so will complaining. Jewel Boyd of Sheraden huddled against a storefront Downtown as she waited for the next bus to McKeesport. She had a simple answer for how her morning was going:
"I'm cold, it's rush hour and they should be running more buses," she said. "And they're not."
Andrew McGill: firstname.lastname@example.org or 412-263-1497. Jon Schmitz: email@example.com or 412-263-1868.