The difference between saving money in the bank where we watch it earn interest, and the rise and fall of the stock market, is that in the stock market both capital and earnings move together.
例如，以同類股做比較、注意公司每一季發表的營業及財務報告等。股價指數與經濟景氣齊飛與把錢存在銀行、視利率高低賺利息不同，股票的漲跌是本、利一起動。