Index ETF =/= Passive investing

好多人覺得買指數基金好穩定，因為覺得基金唔會經常買入賣出。 不過，花旗國Mark Cuban講過，買指數基金其實只係買決定指數成份股公司嘅眼光。每一次加入、剔除或改變成份股，你就已經進行了買賣，所以唔好覺得指數基金唔會經常買入 賣出。

When you "buy the market" by buying SPDRs or QQQQ or DIA, you are thinking that you are investing "passively". Merely tracking the market.

However, as Mark Cuban has said, when you buy an index fund, you are actually trusting the stock pickers of the index. Whether it is the S&P 500 or the Hang Seng Index.

Everytime they change their index portfolio, or weighting, your fund will be trading. So do not think your index fund is as passive as they prsent themselves to be.