According to [1] for 2015, the US #13/35 (in the top 37%, so not the middle) on the list on the OECD ranking of average hours worked per worker. In 2015, the US had a Human Development Index (HDI) of 0.920 tied for #10/188 in the ranking of HDI [2]. The only 2 countries with a higher HDI than the US that works more hours in 2015 than the US is Ireland and Iceland. Iceland in 2015 had a population of 329,425 [3] and Ireland in 2015 had a population of 4,688,464 [4], while the US had a population of 321,773,631 [5]. Given that Iceland has an extremely low population compared to the US, Ireland is the only country of comparable population and HDI where the workers work _more_ than US workers.

In contrast, Mexico works the longest hours according to the OECD ranking, but is #77/188 on the HDI ranking list [2].

[1] - https://en.wikipedia.org/wiki/Working_time#Average_annual_ho...

[2] - http://hdr.undp.org/en/composite/HDI

[3] - https://www.populationpyramid.net/iceland/2015/

[4] - https://www.populationpyramid.net/ireland/2015/

[5] - https://www.populationpyramid.net/united-states-of-america/2...