[alex_stoddard]

This seems like two examples of errors converting decimal fractions to percentages in hacker news in one day.

Very roughly it looks like they should have said 0.1 or 10%.

10% of combinded GDP is very much not an easy investment to make!

[aargh_aargh]

Maybe they're calculating the cost over a 100 years while keeping today's GDP as a yard stick. Though nothing in the article indicates so.