I love numbers, charts and tables - and I'm delighted to see I'm not the only Doctor Who fan who does it.
0thatguy has counted onscreen and offscreen deaths in Doctor Who, and gives us some interesting results.
The chart illustrates how light and blissful season 2 was for the Tenth Doctor - "only" 50 people killed - and how it got darker and darker, with the peak in (my favourite; I'm a masochist) season 4.
Of course, it's not surprising to see that Russell T Davies has killed much more people in his era than Steven Moffat in his - everyone knows that. But look at the huge decrease beween seasons four and five! It's almost 83% decline! And it pretty much stayed this way for the entire Matt Smith's era. If we ever met the Doctor, we should hope it's Eleven because he keeps people around him alive.
Twelve obviously isn't that lucky. I wonder if upcoming season 10 fits the trend, or changes it.
This chart of deaths vs ratings is very interesting, although it has to be said that correlarion between two things doesn't imply one is the reason of another (I've kept
this in my bookmark for few months, waiting for other nice links to share. Take a look). If I had the data I could count the correlation coefficient that's better than just a picture. From the chart, it looks like there is a correlation but it can be deceptive.
(When I think about it, my chart of the seasons ratings would look different and it wouldn't be correlated with the numbers of deaths.)
When I look at the data of deaths in particular episodes, I think of the writers. According to this data, Steven Moffat is the only writer who hasn't killed anyone on screen in season one and three. He hasn't killed anyone on screen in season two and all his deaths in season four were reversed (or people have been "saved"). There're five not-reversed deaths in season five (yay!), four in season six and zero (!) in season seven. That means his one season eight episode, "Into the Dalek", has more onscreen deaths than Moffat's episodes in three previous seasons in total. There are 24 Moffat-created deaths in season eight (it's more than a half of deaths in the entire season) and 16 in season nine (exluding the episodes when Moffat is a co-writer). You know when even Steven Moffat starts to kill people? When the Daleks come.
Seriously, look which episodes have the highest death rate and who the enemies are. Season one: "Dalek" with 32 onscreen deaths, plus the deaths in the finale. Surprisingly, the Slitheen are good in killing, too. Season two? Cybermen and the Daleks. Three? The Daleks and the finale, count the Master in. Four - Sontarans and the Daleks in the finale (there's also Turn Left but it's an episode that's a bit different). Very little deaths in five, six and seven, and then comes, bam! "Into the Dalek". A high rate of deaths, incredible for Steven Moffat. Season nine adds the Zygons to the list ("Heaven Sent" is, again, not a typical episode).
Conclusion? The Daleks are almost always deadly ("Asylum of the Daleks" is an exception) and bring more death than any other alien race. Cybermen, Sontarans, Zygons and the Master are on the deadly list, too. And the Slitheen.
RTD kills, but not always ("Fear her" is death-free)*. Chris Chibnall started with 5 onscreen deaths in "42", and went through 3 in season five two-parter, to 1 and 0 in his season seven episodes. Looks like he just wanted to fit in ;)
It's a shame the specials aren't included in this data but I don't think they would change much. Anyway, it's a good job.
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This is another nice chart related to Doctor Who. A scientific explanation of why Ten is the best Doctor ;)
*ETA: I just found out that "Fear her" is not a RTD's episode, it's Matthew Graham's. I was sure Davies wrote it! So according to the data above, the only episode with 0 onscreen deaths written by Davies is "Love and Monsters", but the people from LINDA are characters we like and care about (as opposed to - not included in the table - Elton's mum) so the emotional impact of their deaths is big. Hence, Russell T Davies kills. Although, I think it would be a good idea to include in the data if a killed character is a random person or a character we know and like/dislike, it makes a difference for the viewers.