Long-run costs and economies of scale — practice question

The table presents the labour market for an economy across four different years. In which year did the labour market experience excess demand?

• Aworking population 19m, unemployment rate 1.0%, job vacancies 180k
• Bworking population 19m, unemployment rate 2.0%, job vacancies 80k
• Cworking population 20m, unemployment rate 1.1%, job vacancies 240k
• Dworking population 20m, unemployment rate 1.5%, job vacancies 100k