For years I’ve been asked: “What’s the best day to book airfare.”

And for years, I’ve answered Tuesday.

The general consensus is that buying airfare on Tuesdays in the early afternoon offers the best chance for snagging the cheapest fares. Airlines typically announce sales on Monday evenings, and competitors have usually responded by 1 p.m. on Tuesdays with price markdowns.

It’s not always the case, but for a long time now, if you bought the cheapest fare it’s highly likely you booked your flight on a Tuesday.

Recently, however, I learned that advice may no longer apply.

A couple of weeks ago, I read a report in The Dallas Morning News with data that supports Sunday as the best day for finding low airfare.

When I saw the headline I was surprised. I’ve always thought the weekend was the most expensive time to purchase flights.

So which is it? Well, I’m not sure it’s a question with a simple answer, but here is the breakdown:

Yes, airlines often announce sales on Mondays. And often, their competitors will respond with a price reduction of their own – if only for a short window of a couple of hours.

So if you see a lower fare on a Monday night or anytime on a Tuesday, take it.

But here is the twist: The Dallas Morning News report cited a study from the Airlines Reporting Corp. that looked at airline ticket purchases between January 2013 and July 2014. It found Sunday purchases to be the cheapest.

The average price for a domestic ticket bought on a Sunday was $432. Next cheapest was Saturday at an average ticket price of $439.

Tuesday? Well, it came in as the cheapest weekday to buy a flight, at an average price of $497 per ticket.

One thing I find interesting in the report is that the sample size is smaller on the weekend. While Sunday and Saturday offered the cheapest average ticket prices, they also had the lowest number of tickets sold, at 6 million and 5.6 million, respectively.

Tuesday had the most tickets sold of any day of the week, with 18 million.

The proof is in the data, I guess. But I find it tough to disregard the time-tested Tuesday trend that’s held true for so many years.

Is this weekend thing a recent trend that will eventually revert back to Tuesdays?

In the current market for air travel, it’s impossible to predict where the industry is going. So my advice now is to comparison shop.

If you really want to book the cheapest fare, it’s helpful to start scoping out ticket prices as early as possible. Say you’re planning to fly to Miami in January. You’ve been looking for a couple of weeks, and the fares are always roughly the same. Then you check on a Tuesday and the fare is $45 cheaper.

Yeah, I’d jump on that.

But if you don’t see a fare reduction on Tuesday, consider holding out until the weekend to check the fares again.

As for me, I’ll continue to buy flights on Tuesdays, but not before I’ve checked out fares over the weekend.

Memphis Daily News managing editor Lance Wiedower’s column appears every other Tuesday in The Daily News and The Memphis News. For more travel inspiration, read his blog at tripsbylance.com or follow him on Twitter at @tripsbylance.