Dwyer and Tanner (2006) say the purchases made by companies, government agencies and institutions "account for more than half of the economic activity in industrialized countries such as the United States, Canada and France."
Dwyer and Tanner (2006)认为公司、政府部门和机构的购买占美国、加拿大、法国等工业化国家经济活动的至少一半。