这些活动现在占美国工资总额的51 ％ ， 而且在雇用大量工人的行业中最为普遍，包括酒店和餐饮服务业，制造业和零售业。
Such activities now account for 51% of US wages, and are most prevalent in sectors that employ large numbers of workers, including hotel and food services, manufacturing, and retail trade.