The last century has witnessed dramatic changes in the world economy. The service (tertiary) sector, which at the beginning of the 20th century was of little importance relative to agriculture and manufacturing, has become the dominant sector today, accounting for 80% and more of value added in...

Job polarization is a widely documented phenomenon in developed countries since the 1980s: employment has been shifting from middle to low- and high-income workers, while average wage growth has been slower for middle-income workers than at both extremes. We document 1) that polarization has...