A recent episode of the excellent More or Less podcast featured a discussion of the ‘micromort’, a unit expressing a one-in-a-million chance of dying. You can apply a number of micromorts to various activities to express the statistical odds of dying because of that activity.
If you assume that the average lifetime is 80 years, then this totals nearly 30,000 days (80 x 365 = 29,200). Averaging one death per 30,000 days, we find the risk of dying, due only to your own, avergae mortality, is about 30 micromorts per average day. We can consider this the background level of risk that your experience during your daily life. By comparison, you add a micromort of risk for every 3 hours you spend in a coal mine. So if you worked for 90 hours down a coal mine this year, you’d double your risk of death from 30 to 60.
Accident statistics provide a good source of micromort calculations. You can add one micromort to your year for every 150 miles travelled in a car due to car accidents Alternatively the same risk applies to just 10 miles on a bicycle or 6 miles by canoe.
The average American’s annual chance of being murdered is 64.8 micromorts. That means 64.8-in-a-million (1-in-15,440) people will be murdered in an average year in the US. Annually, strokes contribute 589 micromorts and cancer adds 1957. Your largest ‘dose’ of micromorts in the Western world comes from heart disease. 1-in-397 people will die in a year from heart disease, meaning heart disease exposes the average person to 2519 micromorts. Of course we get to chose our own micromorts, to a degree. By not smoking you take away a fair chunk of those heart disease micromorts. By exercising and eating healthily, we take them down a chunk more.
You can avoid ever catching a flight and thus not expose yourself to an annual 0.9 micromorts from aeroplane accidents. Of course you’ll never get rid of the 0.06 micromorts you are exposed to by the fact that an aeroplane may fall from the sky and kill you! Sorry about that. Isn’t that weird though? You’re only 15 times more likely to die in a plane accident that you are to be victimised by one – sheesh.
Micromorts allow you to compare personal risk in a whole new way. They allow you to see that the risk of dying from a lightning strike (0.2 micromorts annually) is the same as the risk of being killed by an insect bite. In fact, you’re far more likely to be killed by a co-worker this year (9 micromorts). You are probably aware that you *might* die in a hospital this year – in general, your annual risk is 114 micromorts – but once you’re admitted the risk leaps to nearly 900 micromorts.
The risk of dying from cancer due to living with smoker for a year is the same as the risk of dying from radiation exposure due to living on the boundary of a nuclear reactor site for 30 years: 6 micromorts. You’re ten times more likely to be killed this year by a flood (0.4 micromorts) than by a hurricane (0.04 micromorts) but both are far more likely than you being killed in a bioterrorism attack (0.018 micromorts).
I shall leave you with a scary side-effect of the micromort concept: it makes it very easy to place a monetary value on a human life. If I were to offer to take away one of your annual micromorts for £1, would you accept my offer. what about £10 or £100? Conversely, how much would I have to pay you for you take on an extra micromort of risk?
It may sound bizarre but we make these decisions all the time. When you buy a car you take safety into consideration but you don’t always buy the safest car. This places a value on life. If you pay for medication, your paying to avoid a risk of pain/death to some degree.
Without going into details, it turns out that a micromort is worth around $10. Which makes a human life worth something like $10,000,000 dollars.
[Many statistics for this post found via Stanford Online]