The Paris Region had 5.4 million salaried employees in 2010, of whom 2.2 million were concentrated in 39 pôles d'emplois or business districts. The largest of these, in terms of number of employees, is known in French as the QCA, or quartier central des affaires; it is in the western part of the City of Paris, in the 2nd, 8th, 9th, 16th and 18th arrondissements. In 2010 it was the workplace of 500,000 salaried employees, about thirty percent of the salaried employees in Paris and ten percent of those in the Île-de-France. The largest sectors of activity in the central business district were finance and insurance (16 percent of employees in the district) and business services (15 percent). The district also includes a large concentration of department stores, shopping areas, hotels and restaurants, as well a government offices and ministries.

How many salaried employees lived in the Paris Region in 2010?