Leaked viewing figures show just how valuable The Grand Tour is to Amazon

Reuters has obtained company documents revealing how Amazon's original TV shows have been in driving Prime subscriptions. The figures show that The Grand Tour has been more successful at encouraging sign-ups than any other original Amazon series.

Presenter Jeremy Clarkson recently hit back at reports that The Grand Tour was set to be cancelled. Following a report in the Mail on Sunday that the series could be axed, Clarkson tweeted, "Don't believe the f***ing Mail".

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Now the documents, which have not currently been verified by Amazon, show how the internet giant judges the success of The Grand Tour and other original series.

According to Reuters, one of the figures that Amazon uses to judge success is known as the "cost per first stream". The metric divides how much the show costs to make by the number of people who watch that show first when they sign up for Prime.

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The assumption is that the first show a viewer watches after signing up is the reason they signed up for Prime in the first place. So if people stream The Grand Tour straight after signing up to Amazon Prime, then Jeremy Clarkson and co are credited with securing that membership.

By this metric, the figures show that The Grand Tour season one was the best performing Amazon Original series. While costing a reported $78 million to make, the show pulled in more than 1.5 million "first streams", meaning the show had a "cost per first stream" of $49 per subscriber.

When you consider that a Prime membership costs $99 in the United States, The Grand Tour appears to have been a successful investment.

By comparison, the first season of drama Sneaky Pete created by House showrunner David Shore and Breaking Bad star Bryan Cranston had a cost per first stream of $959 dollars, significantly more expensive than the basic cost of a Prime membership.

The figures seen by Reuters include subscribers in the US and UK as well as Germany, Austria and Japan.

The report claims that Amazon Prime Video drew over five million people to the Prime subscription service by early 2017. It also calculates that around 26 million US Prime members watched television and movies on the service by 2017.

Chief executive Jeff Bezos has been open about the fact that the drive into original content was designed partly to boost Prime subscriber numbers, thereby getting more people to shop on Amazon.

“When we win a Golden Globe, it helps us sell more shoes,” he said in 2016. The leaked documents, however, do not show how much shopping these new Prime Video customers did on Amazon after signing up to Prime.