So, the topic of ratings is an interesting one. Both in the philosophical "Why do we care about them" as well as in the pure numbers crunching way. So, since I'm too tired for philosophy I decided to crunch the numbers. I got the consolidated ratings for series 1-10 and the first six episodes of series 11 and calculated the average numbers of views per episode of each series. I decided to split series 6 and 7 into their automn and spring halves since they both had essentially second first episode, which seemed unfair to me. I also decided to only count episodes 2-5 of series 11 since you complained about people always using episode 1 to say that series 11 has better ratings than the other series.Seems appropriate the ratings are down. Oh! But they aren't..sure..sure..keep telling yourself that. But the consolidated Ratings are way up compared to Capaldi's last season! Hmmm..sure..sure..but they are exactly where Capaldi's were in his first season, so really whats the difference. The new season was supposed to be the reboot. Better ratings.
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The new direction was supposed to raise ratings, not maintain it at its lower levels. Where are all these new fans that were supposed to return it to its glory? The premier was pretty much the only thing supporters of this new iteration point to constantly, but in the end, much like Star Trek STD, Disney Star Wars and such "modern" revamps, they suck.
So, here are the numbers:
Series 1 ---7.924615385
Series 2 ---7.638461538
Series 3 ---7.538461538
Series 4 ---8.040769231
Series 5 ---7.730769231
Series 6A ---7.66
Series 6B ---7.356666667
Series 7A ---7.962
Series 7B ---7.11625
Series 8 ---7.2625
Series 9 ---6.161538462
Series 10 ---5.454166667
Series 11 ---7.89
Sorted by numbers:
Series 4 ---8.040769231
Series 7A ---7.962
Series 1 ---7.924615385
Series 11 ---7.89
Series 5 ---7.730769231
Series 6A ---7.66
Series 2 ---7.638461538
Series 3 ---7.538461538
Series 6B ---7.356666667
Series 8 ---7.2625
Series 7B ---7.11625
Series 9 ---6.161538462
Series 10 ---5.454166667
So, Series 11 (minus it's strongest episode) beats out all of Capaldi's era, all except for half a series of Smith and the middle part of Davies' tenure as showrunner.
That being said I wouldn't go as far as saying that series 11 is widely more successful than the rest of Doctor Who. With the exception of series 9 and 10 all the series got between 7.1 and 8.1 million viewers, so it all seems pretty steady. However, when compared to the immediate predecessors Chibnall's era beats Moffat's, except for half a series. Of course we only have half a series from Chibnall, so this may very well change in the future.
Here's a screenshot of what my spreadsheet, for clarity's sake. My numbers are from themindrobber.co.uk which I hope is a decent source. I cross-checked some of their numbers with Wikipedia and another site and they were identical.

You may notice that the numbers got commas instead of dots, that's because I'm German and so is my Excel and in Germany we use dots and commas in reverse to how they're used in the US, so for example 8,7M is 8 million 700 thousand.
I may have very well miscalculated something here, so if something strikes you as odd please point it out.
I also included an average of views/episode of all series, all of them except series 11 and all of them except for series 9 and 10, just out of curiosity.
What's a baf?"Think like us or You're a baf horrible person!"
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