The City of Wichita’s legislative agenda regarding the Affordable Airfares subsidy program seems to be based on data not supported by facts.
As the City of Wichita prepares its legislative agenda for the Kansas Legislature, the first issue gets off to a rocky start with figures that are not aligned with facts. Probably the largest whopper is the claim of how much has been saved in airfares. The Wichita document states this: “Since 2002, Affordable Airfares has provided $1.446 billion in savings for Wichita Mid-Continent air travelers.”
That is a lot of money. It is certainly exaggerated. We don’t really know how much the subsidy program has saved, as we can not know what would have happened had there been no subsidy program. So we estimate, and here two estimates.
A study from Dr. Art Hall contained this: “Combining the estimated aggregate savings for AirTran and Frontier sums to an annual average range of $30.75 to $39.5 million. (An Evaluation of the Kansas Affordable Airfares Program, Arthur P. Hall, Ph.D., February 2013)
Minutes of a July 2011 REAP board meeting hold “This program also saved air travelers out of MidContinent Airport more than $33.2 million in reduced fares in 2010, compared to 2000.”
So if we use, say, $35 million as the annual savings, then for the 12 years from 2002 to 2014 the savings sum to $420 million. The city claims $1,446 million, or 3.4 times as much. Wichitans might want to ask city hall why there is such a large difference.
The city’s legislative agenda also mentions a presentation given by William S. Swelbar, an aviation industry analyst, reporting “The Wichita airport performance is acknowledged for its unique performance in growth and capacity (Bill Swelbar presentation at WSU Economic Conference).” There are several curious aspects of this presentation.
The slide that shows growth in traffic at the Wichita airport needs to be interpreted with caution. First, note that the scale of the vertical axis does not start with zero. This is something that needs to be recognized. Here’s why: The bars for departures appear to be rapidly rising. The bar for 2013 looks about twice as tall as the bar for 2102. This leads to the impression that whatever it is that these bars represent, it has doubled from 2012 to 2013. That’s because bars on a chart traditionally represent a quantity of something, starting from zero.
When we examine the entire vertical axis of the chart, we see that it does not start with zero. Instead, it starts at the value 12,050, and the entire axis represents a range of 250 passengers per year. This means that the increase in departures from 2012 to 2013, which looks like an impressive jump in Swelbar’s chart — a doubling in value — is an increase from 12,120 to 12,195. This represents a growth of departures of 75 per year, which is 0.62 percent. Or, about 6 flights per month. This is better than a decline, but not by much. (I’m reading the chart and interpreting the height of the bars against the scale, so these numbers could be off a bit.)
It is not deceptive to start a bar chart from a point other than zero, as long as readers are aware of that and interpret the numbers cautiously and appropriately. But that wasn’t made clear in this presentation. These numbers need to be placed in meaningful context. Otherwise, city council members and bureaucrats might jump on this chart and use it as evidence of dramatic changes happening at the Wichita airport when in reality the change is quite mild. This is what has happened.
What about the increase in departures from 2013 to 2014? The presentation by Swelbar was given in October 2014 and would have been based on data available only through June or July. But somehow, Swelbar told the audience how many departures the Wichita Airport would experience in all 2014. I can understand presenting an estimate for 2014, but the number is not presented as such.
The data for the years that are complete also appear to be questionable. For departures, Swelbar shows departures rising from 12,120 for 2012 to 12,195 for 2013 (again, estimating from the heights of bars on the chart). The Bureau of Transportation Statistics shows departures from Wichita in 2012 as 12,037, then declining to 11,984 for 2013. (Click here to view these statistics.) The statistics from the Wichita airport don’t directly report the number of scheduled departures. For what it’s worth, the airport reports passenger count of 1,509,206 in 2012, which fell to 1,508,872 in 2013.
These are problems found on the first page of the city’s presentation. The agenda was presented to the council during a workshop on November 25. The council will vote on adoption of the agenda on December 9, having postponed the vote from December 2.