Time worked at average wage for one hour of light, seconds.
Source: Matt Ridley, The Rational Optimist: How Prosperity Evolves (HarperCollins, 2010), pg. 20.Time worked at average wage for one hour of light, seconds.
Source: Matt Ridley, The Rational Optimist: How Prosperity Evolves (HarperCollins, 2010), pg. 20.