Here's an interesting table from p. 240 of David Willetts's The Pinch of average male life expectancy at the age of 65 in the UK (in other words, in 1950, 65-year-old British men were expected to live to 77.0):

1950: 12.0

1960: 12.2 (+0.2 v. decade earlier)

1970: 12.8 (+0.6)

1980: 14.0 (+1.2)

1990: 15.8 (+1.8)

2000: 18.2 (+2.4)

2010: 21.7 (+3.5) [projected from growth from 18.2 in 2000 to 21.0 in 2008]

So, for every four days you live, you only get three days closer to death? What better excuse for procrastinating?

Now, that's pretty weird. Instead of diminishing marginal returns, we (or at least Brits) are currently enjoying increasing marginal returns. Well, I'm not complaining.