If you went to the movies last year, there's a good chance that you had your feet planted in mystery stickiness for a period of more than 120 consecutive minutes. The Hunger Games: Catching Fire, for instance, was just shy of two and a half hours long. The Hobbit: The Desolation of Smaug kept you glued to the concrete for a whopping two hours and 41 minutes. All told, the five top-grossing (live action) movies of 2013 ran for an average of about 134 minutes. That's more than a 20% increase in length since 1980. In fact, over the past 30 years, the most popular movies have been getting steadily longer, adding about an extra minute of running time annually. What gives?
One factor might be technological advancement. With today's digital equipment, it's easier (and cheaper) than ever to shoot and edit film. (For one thing, you don't need film.) The Academy Awards might also place some upward pressure on running times: long movies tend to fare better at the Oscars than their more succinct counterparts. And theaters have changed, too. The rise of the multiplex means that long movies no longer limit the number of shows a venue is able run daily, since movies can simply play on multiple screens simultaneously. So, putting it all together, does this mean we should brace ourselves for the continued epic lengthening of...well...epics?
Maybe not. It's true that the highest grossing movies have gotten longer over the past three decades, but if we go back another 25 years or so, you'll see that the data paints a very different picture. In fact, if I were writing this post in 1980, it would be about why movies keep getting shorter. At that point, average running time had dropped from an all-time high of 189 minutes1 in 1956 to just 118 minutes by the end of the '70s. The point is, someone with a few decades' worth of data in 1980 would likely have made a woefully inaccurate prediction about the future of popular movies, and that should give us pause about making predictions for the future here in 2014.
There's an important mathematical life lesson to be had here: extrapolation can be dangerous. If you have a model that does a good job of fitting data over a particular range, you should be cautious about using it to make predictions beyond those bounds. This is especially true with linear models because, over a short enough range, almost every pattern of association looks roughly linear. If you're going to extrapolate from a line of best fit, you'd better have a compelling reason to suspect that your data should be linear, and that's clearly not the case with movies. Obviously the recent pattern of growth has to break down at some point: seven-hour blockbusters probably aren't in the cards.
Here's the complete picture, going all the way back to 1927 and the beginning of the feature film as we know it.2
In the early years, movies got longer and longer; then they shortened up through WWII; then grew and peaked in the late '50s and early 60's; dropped off again through the early '80s; and that brings us to the current upswing we see today. So it seems as though movie lengths are somewhat cyclical. And that's probably good news, lest you risk becoming permanently welded to the floor of the theater.
Teachers, want to have this discussion in class? Check out our lesson materials!
1. 1956 was a year of especially interminable films, including juggernauts like The Ten Commandments (220 minutes) and War and Peace (208 minutes), but it also marks a turning point, as we'll see shortly.
2. In that year, the 'talkie' came into its own when The Jazz Singer was released as the first commercial feature-length picture to include synchronized audio dialogue. Unfortunately, it's so incredibly racist that I'm not even going to link to it.