A.股票價格指數(shù)先于經(jīng)濟周期的變動而變動 B.股票價格指數(shù)與經(jīng)濟周期同步變動 C.股票價格指數(shù)落后于經(jīng)濟周期的變動 D.股票價格指數(shù)與經(jīng)濟周期變動無關(guān)