The average vampire who wants to keep people alive is going to take about 2-3 blood points per hunt. That means he hunts every 2 to 3 days. That's about 146 hunting incidents per year. We'll multiply by 1.5x to account for the fact fact that most blood is spent healing, pumping attributes, using disciplines and such though for most vampires this probably happens infrequently. Some vampires might use more blood than others, but others use less. It evens out. This gives us 219 hunting incidents per Year per Vampire.
Next, let's suggest that out of these 219 incidents, 1/10th of them go wrong in some fashion. The Vampire takes too much blood, there's an unexpected witness, the witness remembers the events, or something happens that can cause trouble. This gives us a total of 22 botched hunting sessions per year per vampire. Of these botched huntings, 1/6th of them result in one human being killed on average. Some might involve more, but some might just be very very bad and not result in any, so we'll assume it averages out in this case.
That's 3.65 mortal deaths at the hand of each Vampire per year.
We know that there is, world-wide, about one Vampire per 50,000 people. There are about 6.5 billion people in our world, so that gives us approximately 130,000 vampires worldwide.
Now, first, let's note that the AVERAGE vampire isn't necessarily "responcible" in the manner described above. MOST, however, are. Even the Elders try to avoid getting caught or causing too much trouble that might get traced back to them.
So, 80% of the Vampires fit reasonably in the model above. 15% are worse; they kill 3x the number mortals as the average responcible vampire does resulting in 12 human deaths per said degenerated Kindred. 5% are considerably better; they mostly only eat animals and only really kill people when they have no other choice or when they frenzy. We'll say their mortality rates are 1/10th normal, for .4 per year.
104,000 x 3.65 = 379,600
19,500 x 11 = 214,500
6,500 x .365 = 2,373
Total per Year: 596,473 deaths as a result of a botched and fatally screwed up hunting attempt. It makes no attempt of the other possible causes of death in a year related to Vampires.
This would make, I believe, Vampires the Second Leading Cause of Death in the World -- if anyone knew that they were there. They'd be right behind Heart Attacks (700K per year), and just a ways ahead of Cancer (533K per year) in terms of fatality.
VERY Interesting...
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