Sigh. Here we are again, another year, and yet another uninformative, and actively misleading congestion cost report from Inrix.
More myth and misdirection from highly numerate charlatans.
Burying the lede: Traffic congestion is now lower than it was in 2019, and congestion declined twice as much as the decline in vehicle travel.
Today, Inrix released its latest “Global Traffic Scorecard,” which purports to rank US and Global cities based on traffic congestion levels.Over the years, we’ve reviewed Inrix annual traffic scorecard reports. They’re monotonous in their sameness. Congestion, we’re told, is very bad and very costly. But little of this is true or more importantly, actionable. The estimates of supposed congestion “costs” simply aren’t true because neither Inrix (nor anyone else) has specified how they’d eliminate congestion at a cost less than the supposed dollar value of time lost. Without a clear idea of how one could go about eliminating these costs, the information simply isn’t actionable. As we’ve explained in our “Reporter’s Guide to Congestion Cost Studies,” these reports are rife with conceptual and methodological errors. Today’s Inrix report is still marred by these same problems.
There are a couple of improvements in this report from the rest of the literature. Inrix spends some time on traffic crashes and deaths, and notes the troubling increase in crashes despite the decline in vehicle miles traveled. To their credit, Inrix this year has carefully avoided claiming or implying that expanding highway capacity would somehow reduce congestion. That claim has been definitively and scientifically debunked. We know that, thanks to the fundamental law of road congestion, that more road capacity will simply induce more car travel, fully offsetting any supposed congestion-busting benefits. But that won’t stop many Inrix clients, notably state highway departments, from pointing to Inrix data as the reason they should be given tens of billions of dollars to widen roads. And that’s apparently the real purpose of the Inrix report, to curry favor with potential highway department clients.
Most of what we’ve said about previous Inrix congestion reports apply with equal force to this one. We’ll highlight a few points.
First, if you read closely, you’ll learn that time lost to congestion in the US is still lower than it was three years ago, prior to the pandemic. Inrix reports that congestion time losses were 20 percent lower in 2022 than 2019, 4.8 billion hours, down from 6 billion hours. This is good news.
Second, that reduction in congestion should be celebrated, and should also be a teachable moment. If we’re so concerned about congestion, then the experience of the past few years ought to be studied to see if we can learn something. Right off the top, there’s a really important fact that’s buried in the Inrix report: While congestion declined by 20 percent from 2019, traffic (vehicle miles traveled or VMT) went down by just 9 percent.
The fact that congestion declined more than twice as much as VMT is a critical observation: It means that demand management can reduce congestion, and that modest changes in travel volumes produce disproportionately large improvements in transportation system function. If instead of managing demand with a pandemic and lockdowns, we did something a little more nuanced, like road pricing, we could achieve real and lasting congestion reductions. That’s exactly the sort of actionable information that ought to be in this report, but which is missing.
Third, there are a whole bunch of other important things that are missing as well. If you search through the latest Inrix report, here are some words you simply won’t find: “sprawl,” “pollution,” “emissions,” “carbon,” “climate,” “induced demand,” “pricing,” and “tolling.” Trying to talk about urban transportation systems without considering their effects on these other pressing problems is a measure of how detached the UMR is from the reality of the 21st century. Transportation is the leading source of greenhouse gas emissions in the US, and these emission are increasing. The Inrix report exists solely to feed an overriding obsession with speed and congestion as the. criterion for setting transportation policy.
Fourth, in reality the city rankings are meaningless. The measure Inrix uses totally ignores the differences in distances among Metro areas. The fact that you have to drive twice as far, on average, in Houston or Atlanta as you do in Chicago or Boston, doesn’t figure in to the “cost” of commuting. As we’ve shown, this particular measure inaccurately penalizes compact cities where people make shorter trips, because it looks only at the difference between peak and non-peak travel times. Cities with shorter travel distances generate less car travel (vehicle miles traveled), emit much less greenhouse gas emissions, and save their residents billions of dollars in avoided travel costs compared to sprawling, car-centric metro areas. The best way to reduce the cost of transportation, and time lost is to have more compact development, something we’ve demonstrated in in our previous analysis. And while the Inrix report spends a lot of time talking about the added burden of high gas costs, it completely leaves out the fact that higher gas prices are much more burdensome in cities and neighborhoods where people have to drive long distances.
Fifth, the Inrix rankings are a profoundly car-centric view of the world. Inrix likes to tout its “big data” noting that its estimates are drawn from billions of data points. But those data points are almost entirely cars and trucks. There’s an old saying “if you don’t count it, it doesn’t count.” They leaven their reporting with a handful of statistics on bikes and pedestrians, but these are drawn from the rare reports compiled by cities, not from Inrix data. The car and bike data, and the actual variation in commuting distances, simply don’t figure into the Inrix rankings. In short, if you don’t travel by car, you really don’t count in the Inrix rankings.
Sixth, there’s no evidence that driving faster makes us happier. Inrix and other congestion reports prey on our sense of annoyance and victimization about traffic congestion. It’s all these other people who are slowing us down, and we’d be better off if they were gone and we could drive faster. But cities that are optimized for speed simply sprawl further and require more driving, making us more car dependent and costing us more money.
Finally, it’s truly disappointing that such a rich and detailed source of information should be used largely for car-based propaganda. Reports like these aren’t really designed to help diagnose or solve problems, but simply to generate heat. They’ll be used in predictably misleading ways by road-widening advocates. More or bigger data doesn’t help us solve our problems when its filtered through this incomplete and biased framework.
Our reviews of previous Inrix Scorecards
In 2018, we lampooned the predictable alarmist tone of the congestion report:
Cue the extreme telephoto shots of freeways!
Wallow in the pity of commuters stuck in traffic because of all those other people!
Wail that congestion is getting worse and worse!
We noted that the 2017 Inrix report adopted a new and more expansive definition of congestion costs which further inflated its estimates.
Older studies like TTI, estimated dollar costs based on the additional time spent on a trip due to congestion: So if a trip that took ten minutes in un-congested traffic took a total of 15 minutes in a congested time period, they would monetize the value of the five minutes of additional time spent. The Inrix report appears to monetize the total value of time spent in congested conditions, i.e. anytime travel speeds fell below 65 percent of free flow speeds.
In 2016, we gave the Inrix report card a “D”
In 2015, we pointed out that the Inrix study had a number of contradictory conclusions, and that Inrix had “disappeared” much of its earlier data showing that high gas prices had demonstrably reduced traffic congestion in US cities.
For more information and analysis about the conceptual and methodological problems in these “congestion cost studies,” see our Reporter’s Guide.