Living to 150: A quick reality check

Our fact challenged Treasurer, Joe Hockey raised some eyebrows when he suggested that we need to reform Medicare because children born today might live to 150. He got some support from University of New South Wales faculty of medicine dean Peter Smith, who cited the increase in life expectancy over the last century, from 55/59 (for men and women respectively) in 1910 to 80/84 today.

There’s an apparent paradox here: If life expectancy is 80/84 years today, how can a newborn child expect to live 150 years. The answer is that “life expectancy” is nothing of the sort. It’s the average age at death if current age-specific mortality rates remain unchanged. On average, people born in 1910 actually lived well beyond their “life expectancy” because death rates fell through their lifetime. So, if medical progress continues, people born today may live, on average, well past 80/84.

But how much more? Unfortunately, on past indications, not much more. Most of the 20th century extension of life expectancy came from a reduction in death rates for the young. A 65-year old in 1910 could expect to live to 76/78 (since death rates don’t change much over a decade, that’s an actual expectation not just a statistical construct). Today, that’s increased to 84/87, from 11/13 years of extra life to 19/22. For Hockey to be right, over the next 100 years or so, the conditional expectancy has to rise five-fold, to 85 years. The basis for all this, it seems, is a 2011 press release of the kind we see every week or two announcing a breakthrough that might, perhaps, lead to a cure for this or that disease.

But even in the unlikely event that this extension of life occurs, what possible relevance could it have to the amount we should pay for medical care today? Even under current rules (which would certainly change with extended life expectancy) Hockey’s hypothetical Methuselah wouldn’t be eligible for the age pension until 2085 and (given the anti-aging breakthrough he hypothesises) wouldn’t seriously burden the health care system until well into the 22nd century. Coming from a government that dismisses concerns about climate change as a problem for the indefinite future, this solicitude for Treasurers yet unborn seems misplaced.

Update Via Twitter, I discover that the source of Hockey’s claim is someone called Aubry de Grey, who is obviously in the tradition of wealthy British eccentrics, with his own foundation, journal and so on; a much more appealing instance of this kind of thing than Lord Monckton, but still not to be taken seriously.

Further update Defending Hockey’s silliness, Mark Kenny makes the point that what Hockey actually said (restating de Grey) was that it is “remarkable that somewhere in the world today, it is highly probable, a child has been born who will live to be 150”. This shift from mean to maximum helps the demographic plausibility of Hockey’s case, but only marginally (we still need an advance of nearly 30 years on 122, the longest lifespan ever recorded), but it makes the argument even weaker. Suppose that some child in, say, China is going to live to 150. What possible impact can that have on our health system. More generally, what can it matter to the budget if a handful of people live very long lives. It’s the average (measured by numbers like life expectancy at 65) that matters. As an indication of the minuscule scale of the fiscal problem posed by those with very long lives, there are currently only about 4250 Australians aged over 100, amounting to about 0.02 per cent of our population.

Yet further update It’s worth pointing out that, with pension age eligibility rising from 65/60 when the age pension was introduced around 1910 to 70/70 by 2035, men will have lost half of the extra retirement years gained from higher life expectancy and women the whole gain. The big problem we face is underemployment of prime-age workers, not the fact that we aren’t dying early enough.

Increasing trend keeps on increasing

Unsurprisingly, 2014 was the warmest year so far in the incremental record, as measured by NOAA and NASA. A few quick observations

* It’s silly to base global judgements on local observations. Still, living through January 2015 in Queensland, it’s easy to believe that the warming trend has continued into the New Year

* There’s nothing special about a calendar year. The first part of 2014, particularly February, was cooler than the rest of the year. So, it’s a safe bet that the 12 months ending Feb 2015 will be even warmer than the 12 months ending Dec 2014

* The biggest source of short-term fluctuations is the El Nino cycle, responsible for the very warm year in 1998 that is the basis for so much silly talk about “no global warming for x years”. 2014 was the first record year without a full-scale El Nino, though it kept threatening to emerge. Predictions are mixed for 2015.

* Of course, this long-expected news had no effect on denialists. But, like anti-vaxers, they are no longer getting the kind of “balanced” hearing they have counted on for so long, at least outside the Murdoch press. It’s now generally recognised that climate science denial isn’t a scientific viewpoint but a tribal shibboleth, and this is reflected in news coverage.

Sandpit

A new sandpit for long side discussions, idees fixes and so on. Unless directly responding to the OP, all discussions of nuclear power, MMT and conspiracy theories should be directed to sandpits (or, if none is open, message boards).

Predictions for 2015

Prediction is very difficult, especially about the future, as Niels Bohr is supposed to have said. I’ve certainly found it so. Apart from the obvious possibility of being wrong, there’s the risk that others will misrepresent you. But, as long as you don’t take it too seriously, it’s helpful to frame discussion around a sharp prediction. So here are three for 2015

1. Peak Oil: I predict that global oil production (conventional and shale etc) will decline in 2015 and will never again reach the peak level of 2014. My reasoning is that 2014 supply can’t be sustained at prices below, say, $75, and (given a downward underlying trend in the developed world), 2014 demand won’t be reached again at prices above $75.

2. The End of Bitcoin: I’ve written in the past that “Bitcoins will attain their true value of zero sooner or later, but it is impossible to say when.” However, I now think the necessary conditions are in place for most holders of Bitcoins to recognise that their asset consists of used-up computation cycles with zero value. In particular, because mainstream merchants now accept Bitcoin (which they immediately sell), it’s possible for hardcore believers to dispose of their holdings without explicitly betting that the price will fall. Of course, the price won’t fall precisely to zero, but it should be well below $100 by the end of the year, and below $10 not long after that.

3. The Paris conference on climate change, will produce a half-baked compromise, which nevertheless represents progress towards stabilization at 2 degrees of warming: OK, this is pretty much a no-brainer, given that this is what we’ve been seeing ever since Kyoto in 1997, but I want to be sure of getting at least one right.