2007年4月30日

如何選擇折現率?(九)

也許有人到現在還未看到筆者提到「資金成本」(Cost of Capital),可能忍不住會問:那教科書上提到的或專家所謂的資金成本加權平均資金成本(WACC, Weighted Average Cost of Capital)又是怎麼回事呢?我們不是應該用它做為折現率的嗎?(注意:此處所謂的「資金成本」是指對公司整體而言,而非針對某筆特定借款。)

筆者原來是準備刻意不提的,有人問了,也就順便說一下。既然我們是以巴菲特的價值投資理念為基礎,讓我們先聽聽巴菲特怎麼看所謂的「資金成本」:

Charlie and I have not the faintest idea what our cost of capital is and we think the whole concept is fairly crazy. Frankly, I’ve never seen a cost of capital that makes sense to me.---Warren Buffett

"I've listened to many “cost of capital” discussions and they've never made much sense. It's taught in business school and consultants use it, so Board members nod their heads without any idea of what's going on."
---Warren Buffett, 2001 Annual Meeting


有時巴菲特說得更直接:
“A corporation's cost of capital is 1/4 of 1% below the return on capital of any deal the CEO wants to do.”---Warren Buffett, 2001 Annual Meeting

(筆者註:表示資金成本的數字可以為了某種目的而被任意操弄出來)

Munger也曾對「資金成本」表示過意見:
"Obviously, consideration of costs is key, including opportunity costs. Of course capital isn't free. It's easy to figure out your cost of borrowing, but theorists went bonkers on the cost of equity capital. They say that if you're generating a 100% return on capital, then you shouldn't invest in something that generates an 80% return on capital. It's crazy."
--- Charlie Munger, 2001 Annual Meeting

綜而觀之,巴菲特及Munger都建議投資人最好不去理會資金成本的概念,免得走火入魔,傷了自己。既然如此,投資人也不必管它資金成本是如何計算的了。

但不要以為他們是說「資金的成本」不重要,資金的成本很重要,只是說學術界或投資界所用的「資金成本」這個概念與定義不可取。巴菲特為了避免旗下經理人因擁有多餘的資金而會受到各種投資案的誘惑,進而做出不理性的投資決策,因此在融資給其下公司經理人時會要求一定的利率---或是所謂的障礙率(Hurdle Rate),來鼓勵旗下經理人把投資報酬達不到障礙率的多餘資金繳回給巴菲特做更好的運用。

巴菲特以往設定的障礙率通常為15%,對那些旗下經理人來說,取得資金的成本就是15%,在評估投資回收時自然會期望報酬率高於15%,也就是會用15%做為折現率來估算投資方案的價值。如你硬要管這15%叫做「資金成本」也行,但除了使你的觀念更加混淆外,對你沒有任何好處。因此筆者建議讀者應該如同對待所謂的Beta一樣,徹底忘了「資金成本」的概念吧

假如你還不死心,非要知道「資金成本」是什麼,那你可以參考這裡:Cost of capital (警告:很多數學公式)

1 則留言:

小白 提到...

我想最基本的原因是學術界使用的資金成本定義又引入了beta這個荒謬的變數