25 years of airfare data from Salt Lake City — what can we learn from the ups and downs?

Why and when do prices take off — and drop — for some routes.

(Chris Samuels | The Salt Lake Tribune) Airport operations at Salt Lake City International Airport on Monday, May 23, 2022.

I’d really like to go on vacation.

After a tumultuous Jazz season and a couple of years of writing data columns, I’d like to take a week off somewhere. But I’m on a journalist’s salary, meaning that I’m going to be price-conscious about my trip. Where can I go — and what airfare should I book — to get the best bang for my buck?

That was the question that got me looking into airfares out of Salt Lake City, and, of course, I’m hardly alone in doing so. But while investigating it beyond the usual flight search tools, I came across the United States Department of Transportation’s database of airfares since 1996. It’s a cool, rich data set, and it tells some interesting stories.

First of all, feel free to play around with the below tool. Choose any city you like to look at the available data, which counts flights in both directions from Salt Lake City International Airport and that city. First-class and economy-plus fares are included in the average, but free tickets given by frequent flyer programs and the like are not.

Any data point you roll over with your mouse or select with your thumb on a mobile device then will show more information: what the largest airline was on that route in any given quarter, what that airline’s fare was, what the cheapest airline was on any given route, and what that cheap fare average was.

You’ll also notice some of the more minor cities have some time periods in which data is missing — that means that they weren’t one of the top 1,000 traveled routes in the United States during that quarter.

If you’re like me, when you click around in a tool like this, you start to notice some trends. Here are some I discovered:

Overall airfare trends

Here’s how airfare trends have developed overall to and from Salt Lake City since 1996:

Note that these aren’t all flights out of Salt Lake City, just those in the top 1,000 data set. But they still cover the vast majority of air traffic every quarter. In the past quarter century, the average airfare has jumped from $142 in 1996 to $210 in 2021.

That sounds like a big increase but remember: inflation. Something purchased in 1996 for $142 would generally be expected to cost $245 today, so $210 actually reflects a significantly cheaper airline ticket than it was before.

You’ll notice that these airfares are definitely cyclical, too, especially in the 2010s. First-quarter airfares are more expensive than the rest of the year. It’s also worth noting that big dip in prices paid in airfare during the pandemic, which has since recovered. In this unusual 2022, airfares are up 20% to 30% right now compared to earlier in the year, according to Delta CEO Ed Bastian.

Note also a growing difference between the largest carrier — that’s Delta on the majority of routes from Salt Lake City — and the cheapest carrier — which turns out to be Southwest on about half the routes covered in the data set. That doesn’t necessarily mean that Delta is always more expensive than Southwest, but perhaps its premium options have resulted in the carrier getting more money per ticket than Southwest’s flatter model.

Interesting (to me) differences in markets

When I go through each of these cities, I’m sometimes surprised to see where there has been significant growth — in passengers or airfare — and where there hasn’t.

The number of passengers traveling to and from Las Vegas, for example, has stayed relatively flat from year to year: About 1,000 passengers a day were on that route in 2021 and in 1998. But travel to and from the Dallas/Fort Worth area has exploded — from about 500 passengers a day to over 1,200 in recent quarters. As the number of passengers has soared, the fares to get to and from Dallas have dropped.

Meanwhile, flights to cities that aren’t considered hubs have seen greater fare increases than their counterparts. Flight prices to Albuquerque, N.M.; Boise; Reno, Nev.; Spokane, Wash.; and Tucson, Ariz., have more than doubled over the past 25 years, outpacing inflation.

Different markets are cyclical in different ways, too. Travel to New York City explodes during the first quarter, while travel to Seattle and Portland, Ore., is highest in the third quarter of most years. Is that just because of the difference between business and tourism travel? I’d take a winter vacation in the Pacific Northwest over the Northeast, but it seems like I might be alone in that.

The impact of low-cost carriers

While I don’t always know why airfare or traffic rises in one place or another, sometimes the reasons are obvious in the data.

Take a look at the airfare to and from Salt Lake City and Denver.

There’s a huge jump in travel between those cities in the beginning of 2006 — and a huge drop in airfares — from an average of $156 down to $91 in just a couple of quarters. What happened?

Well, Southwest happened. It entered Denver’s airport at the end of 2005. Before then, the cheapest carrier, Frontier, charged about $150 to get to Denver and, all of a sudden, Southwest was selling tickets for $74.70. Frontier slashed its prices to compete, too, selling tickets for $83.

By 2011, though, Frontier was now the cheapest airline in the market, selling tickets to Salt Lake City for $101 while Southwest was, on average, at $110. The competition between the two carriers ensured that the prices between the two cities stayed cheaper than the early 2000s — even though Delta has been the largest carrier since 2017.

But Frontier got Southwest back in the Chicago-Salt Lake City route. In 2014, Southwest was charging a whopping $250 to get to or from Chicago. Frontier undercut it, selling tickets for an average of $116 in 2015. Southwest lowered its fares by $100 to keep up — and, interestingly, airline traffic to and from Chicago rose by 30%.

I love when corporate wars are reflected in the data.

Maybe it makes me a nerd, but I could play with this sort of data for hours, learning about the best times and the market conditions that lead to the best prices to and from my home city. I’m curious, too, what my readers can learn by going through the data themselves.

And, heck, maybe I can use these trends to time that next vacation of mine just right — and relocate my data hounding to the beach.

Andy Larsen is a data columnist for The Salt Lake Tribune. You can reach him at alarsen@ sltrib.com.

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