It's a well known fact that GDP per capita is well correlated with other indicators made by organisations with a liberal agenda, such as the HDI - so much that it is problematic both for these organisation, and for a usual neoliberal opinion (with diminishing marginal returns).
Maybe they are diminishing marginal returns with money - just like with human life, after the 1000th year we might get bored, but we don't see them because we look at a too small scale (a mere 75 years of life, with many disabilities in the end)
EDIT : As usual, I don't care for the downvotes down to -1, but instead of a lazy click, could you please take 10 seconds to expose facts if you want to refute my points?
Downvoting means "does not bring anything to the discussion", it does not means "I hate what you think". Facts please. Please bring me shame for how wrong I am, (with references if possible).
Until then, here are my references:
First hits on google : correlation between GDP per capita and HDI : "Human Development Index HDI is advanced as being a better indicator than GDP per capita... BUT look at a plot of the correlation between HDI and GDP/capita or all countries... There is today a very strong correlation"
http://www.gapminder.org/news/hdi-surprisingly-similar-to-gd...
"The concepts of diminishing marginal returns on money" in simpler terms on a blog: http://www.getrichslowly.org/blog/2010/06/16/the-marginal-ut...