講稿15/21
股價由便宜到貴或貴到便宜的時間很漫長
往往長達5年甚至10幾年
中碳在2009年之後才漲上來，
之前好幾年在便宜價以下，
同學一直在問中碳怎麼都不會變貴？
2014年漲到200元又改問我怎麼都不便宜？
The transition of a stock price from cheap to expensive — or from expensive back to cheap — is often a very long process, frequently lasting 5 years or even more than a decade.
China Steel Chemical only began its major rally after 2009. Before that, the stock had traded below what many considered a cheap valuation for several years. Back then, my students kept asking me, “Why does the stock never become expensive?” Then in 2014, when it surged to NT$200, they started asking, “Why does it never become cheap again?”
可是大部分人只做波段，
不像巴菲特抱10年以上。
影響波段漲跌，獲利成長和GDP的力量更強，
接到大訂單會讓股價漲一波；財報不如預期則大跌一段。
But most investors only engage in swing trading,
unlike Warren Buffett, who holds stocks for over 10 years.
The forces that truly drive short-term price swings, corporate profit growth, and even GDP are far more powerful:
Securing a major order can send a stock surging in one wave; missing earnings expectations can cause it to plunge sharply.
大盤也具影響力，所謂「覆巢之下無完卵」。
當大盤疲弱時，個股即便很便宜仍可能持續下跌；
反之，在大多頭市場貴了還會漲到更貴。
市場本益比、席勒本益比，乃至巴菲特指標 (股市總市值/GDP) 可以測量市場貴淑卻不知反轉，預知何時反轉才能研判趨勢。
The broader market is another powerful force; as the saying goes, "under an overturned nest, no egg remains unbroken." When the market is weak, individual stocks can keep falling even if they are already cheap. Conversely, in a raging bull market, expensive stocks can get even more expensive.
Market PE ratios, the Shiller CAPE, and even the Buffett Indicator (total stock market capitalization to GDP) can measure how expensive or cheap the market is, but they cannot predict turning points. To assess the market trend, one must be able to anticipate when a reversal will occur.
只有GDP年增率可以抓到大盤轉折
底下這張圖從1990年以來到現在，是相當完整的一張圖。
這個現象過去都成立就別懷疑這次會不準。
Only GDP year-over-year growth can reliably capture major market turning points.
The chart below, covering the period from 1990 to the present, provides a very complete long-term picture.
Since this pattern has held consistently in the past, there’s no reason to doubt its validity this time.