The release of Avengers Infinity War is imminent but the co-director has reported it is likely to be at least two and a half hours. This doesn’t feel surprising; the current general sentiment is that films are getting longer – too long, even. And I’ll be the first to admit that I feel the same way. I’ve even tossed the idea of an interval around now that everything seems to be over two hours long.

But upon some minor research, I began to realise this might not be the case. Comparing the top 50 films from last year, and then every five years over the last 20, the average film length really hasn’t changed that much, hovering around the 120 minutes mark. In fact, there were more films over two hours in 1997 than there were last year!

So why do we feel like films are getting longer? My first thought was that it was the rise of the Marvel Cinematic Universe with their epically long films – which average at a considerable 127 minutes. The fact that there have been more Marvel films released over the last two years than the first four of the franchise doesn’t help. Combined with the end credit scenes keeping viewers in their seats right until the end, I do think they are making a significant contribution to this feeling. But, equally, Marvel’s films haven’t actually been getting longer: Dr. Strange, for instance, was less than two hours.

So where else is this coming from? Well, films are longer now than they were in the 80s. For example, the average runtime in 1987 was 106 minutes, twelve minutes shorter than last year. However, it’s not the average that I think is the biggest factor. Returning back to 1987, 18 of the top 50 films ran at around 90 minutes compared to just six last year. Over the last 20 years the number of around 90-minute films has been dropping, with films around 112 minutes becoming more and more popular. And I think this is the biggest factor, the loss of the 90-minute film. As a generation who grew up on these, their disappearance comes across as sad and totally unnecessary. Lady Bird showed us that it’s still possible to make a mature 90-minute film in 2017 – other films should follow suit.