index number of retail prices英 [ˈɪndeks ˈnʌmbə(r) ɒv ˈriːteɪl ˈpraɪsɪz]美 [ˈɪndeks ˈnʌmbər əv ˈriːteɪl ˈpraɪsɪz]【经】零售价格指数经济