Ok, lets say there are only two roads in the country...the M25 and a short stretch of road with junctions everywhere, traffic lights, speed bumps, the works.
Now, we have accident figures for BOTH roads. It says 13% of fatalities are contributed to by speeding. We also have figures for the percentage of people speeding (but we ONLY have that for the M25). There isn't a speed camera on the short stretch of road so it can't be included in the statistics.
It is clearly wrong of us to use the figures of the M25 and use them to predict the number of accidents caused by speed on the 'short stretch of road' because they are completely different types of road. However, this is what you've done here - hence the weird (...and wrong) conclusion.
It's like me saying pedestrians are unbelieveably safe to cross on the motorway! The percentage of the overall number of pedestrian deaths on normal roads is FAR higher than on the motorway...therefore the motorway is a far safer road for people to cross than other roads. So we should scrap normal roads as they're too dangerous to cross, instead we should replace them all with motorways and cut out nearly all pedestrian deaths. Can you see how ridiculous this conclusion is...but it's using exactly the same logic you're using John!
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