Read more from Slate’s Summer Movies special issue.

When The Dark Knight earned $158 million in its opening weekend last summer, journalists went gaga over the possibility that it would unseat Titanic as the all-time domestic box office leader. But the race was utter bunk. Accounting for inflation, the true record holder is Gone With the Wind, which—in 2009 dollars—earned over 50 percent more than Titanic and almost three times as much as The Dark Knight. Rhett Butler doesn’t give a damn about Jack Dawson, let alone Bruce Wayne.

Every summer, journalists engage in this brand of misleading speculation. Even when there isn’t an all-time contender like The Dark Knight, other records trip us up. For instance, in 2007, journalists proclaimed The Bourne Ultimatum the top August opening ever, but when you account for inflation, it’s surpassed by 2001’s Rush Hour 2 and 2002’s Signs. While this summer’s Star Trek ($247 million-plus) seems light-years beyond its predecessors, it actually only inched by 1979’s Star Trek: The Motion Picture, which made $235 million in 2009 dollars.

The problems with our growing fixation on box office figures—they don’t account for costs of the film, they don’t include home-entertainment revenue, etc.—have been chronicled in the past. But as long as we continue to indulge this obsession, shouldn’t journalists at least factor in inflation, instead of pretending that it doesn’t exist?

Journalists like to ignore this basic economic principle because, for one thing, “Johnny Depp’s best weekend ever” is a more exciting headline than “Johnny Depp’s 14th-best weekend ever in inflation-adjusted dollars when starring in a Tim Burton-directed children’s novel adaptation.” And perhaps journalists don’t care because the public doesn’t, either. As readers, we get excited about records being broken. As moviegoers, we feel reassured knowing that everyone in America saw the same blockbuster as we did last weekend. But there’s good reason to care about accuracy.

Cinephiles, at the very least, should care, since precise figures can help boost the status of classic films. Lay readers, who now follow the box office as if it’s a sport, should recognize that ignoring inflation is like comparing the world record for the 100-meter dash to the record for, say, a 3-meter dash. That’s a more apt comparison than you might think: The average ticket price in 1939 (23 cents) is 3 percent of the price in 2009 ($7.18). Granted, those who follow box office races as indicators of the quarter-to-quarter financial health of media companies have no reason to heed inflation. But for others in the industry—such as competitors (and shareholders) of companies whose executives use box office figures to brag—accurate figures could provide useful perspective.

Besides, what we really want to know is not how many $1 bills will be dumped onto the Warner Bros. lot when The Hangover finishes its run. We want to know the impact a particular film has had on the country and on our culture. The real question is: How many people have actually seen The Dark Knight or Transformers 2 or whatever the movie of the moment might be?

Ideally, studios and exhibitors would just tell us the raw number of tickets sold. Since they don’t, Box Office Mojo’s inflation-adjusted all-time top 100 list attempts to measure just that—translated into money terms. It takes the film’s gross and divides it by the average ticket price in the year the film was released to find total attendance.

It then multiplies that figure by the average ticket price in 2009 to find its gross in today’s terms (since it’s hard to wrap our minds around a figure like “74 million tickets sold” when we’re already trained to think about money).

Box Office Mojo’s nonadjusted list is dispiriting: A few Spider-Mans here, a couple of Shrek sequels there. All but two of the top 20 have been released since 1993. But the real list is packed with cultural icons. Rounding out the top five are Star Wars, The Sound of Music, E.T., and The Ten Commandments. The Graduate, the anthem of a generation, is stuck down at 380 when you ignore inflation but rises to 18 when you don’t. Snow White and the Seven Dwarfs is 108 on the nonadjusted list, trounced by every Pixar movie except A Bug’s Life. Adjust for price increases, and it passes them all, to no. 10.

Box Office Mojo’s method is far from exact, as the site’s president, Brandon Gray, confessed in a recent conversation. Box office data from before the 1970s are spotty, requiring some Hollywood archaeology to piece together estimates. The site’s dependence on average ticket price is also problematic. Certain movies sell a higher proportion of children’s tickets (which are discounted) or do better in big cities (where tickets are pricier). In the old days, big-event roadshow movies like The Sound of Music would cost more than other films. Plus, the site doesn’t recognize that the cost of a movie ticket has risen faster than the consumer price index. In other words, a ticket to Up in 2009 is more expensive in relation to other items people can buy than a ticket to Gone With the Wind was in 1939.

Population growth is another complication. If our measurement is the number of tickets sold, isn’t Gone With the Wind at a disadvantage as compared with TheDark Knight because there were fewer than half as many people in the United States in 1939 than there are now? Should our measurement be the very unsexy “number of tickets sold per 100,000 people”?

Exactitude is impossible, but a simple acknowledgement of basic economics would be a giant leap forward. So this summer, let’s all strive for accuracy when discussing box office feats. (That goes for you, too, Broadway, and your suspect use of the term “house record.”) Journalists who don’t think they have time to care about price increases can subscribe to Box Office Mojo’s paid service that adjusts most charts for you. And readers, in turn, should refuse to listen to statistics that lie. That way, when the next Gone With the Wind comes along, we’ll know how to recognize it.