未來8年股息和最後賣價算出來之後即可代入折現公式,
公式變成一元八次方方程式,
在國中因式分解教過如何解,
同學有興趣上來解解看嗎?國中數學而已。
不用自己解,Excel有一個函數IRR
可以算出預期報酬率 r = 10%。
Once the dividends for the next 8 years and the final selling price have been calculated, they can be substituted into the IRR equation. This formula can be transformed into a one-variable eighth power equation that can be solved using factorization, which is a math concept that students learn in junior high school. However, students do not necessarily need to solve it themselves, as Excel has an IRR function that can do the calculations. The expected return can be calculated as r = 10%.
IRR(-47.0買, 3.51息, 3.67息, …, 4.18息, (4.29息+58.7賣))
= 10% = r 預期報酬
IRR (-47.0 buy, 3.51 dividend, 3.67 dividend, …, 4.18 dividend, (4.29 dividend + 58.7 sell))
= 10% = r expected return

10%不够好,因我們要求的淑價預期報酬率15%,
所對應淑價是多少?
代入NPV函數即得35元。
A 10% expected return is not sufficient, as a 15% expected return is required for a cheap price. What constitutes a cheap price is not specified. However, when the NPV function is substituted, the result is $35.
NPV(15%, 3.51息, 3.67息, …, 4.18息, (4.29息+58.7賣))
= 35.0 淑
股價跌到35元以下買,每年報酬率才有15%才夠便宜。
NPV(15%, 3.51 dividend, 3.67 dividend, …, 4.18 dividend, (4.29 dividend + 58.7 dividend))
= 35.0 S
If the stock price falls below $35, then buying it can be considered cheap enough, as long as it provides an annual rate of return of 15%.
何時賣?貴了,預期報酬率 0,
所對應貴價一樣代入NPV得出貴價86.1元。
NPV(0%, 3.51息, 3.67息, …, 4.18息, (4.29息+58.7賣))
= 86.1 貴
When should you sell a stock? You should sell when the stock becomes expensive, and the expected return drops to 0. An expensive price can be determined by substituting it into the NPV equation. For instance, a price of $86.1 is considered expensive.
NPV(0%, 3.51 dividend, 3.67 dividend, …, 4.18 dividend, (4.29 dividend + 58.7 dividend))
= 86.1 pricey
貴了就該賣掉,因貴了的預期報酬率為負,
表示再抱下去總報酬只會更少不會更多。
If the stock price is deemed pricey you should sell it because the expected return is negative. This means that if you hold on to the stock, the total reward will only decrease, rather than increase.
貴淑價於財報出爐和除權時會變動。
預期報酬率除息時將上升。
Cheap and pricey prices can change when financial reports are released or when ex-rights dates occur. The expected return is expected to rise on the ex-dividend date.
IRR是投資學中必教的公式,
但真正用它作為買賣股票依據的人卻寥寥無幾,
甚至連投資學教授也很少實際應用。
原因在於學校的投資課程從未深入探討如何選定 IRR所需的關鍵參數,
而這恰恰是決定 IRR公式能否實用的核心所在。
The IRR formula is a fundamental concept taught in investment courses. However, in practice, few investors use it to buy and sell stocks. Even professors who teach investment courses rarely use the IRR formula because the course curriculum often neglects to cover how to choose parameters, which is the key to making the IRR formula feasible.

當ROE過高時,用 IRR計算預期報酬率,
結果往往會高得不切實際。
這並不是公式本身有誤,
而是因為在現實情況下,超高的ROE難以長期維持。
In situations where ROE is extremely high, the expected return calculated by the IRR formula will be unreasonably high. However, this is not a formula error. In reality, it is unlikely for an ultra-high ROE to persist over many years.
當預期配息率過高,IRR計算出的預期報酬率卻可能低到不合理。
例如,UL的本益比僅23倍,但計算出的 IRR卻為-11%,顯然不合常理。
If the expected payout ratio is too high, the expected return calculated by the IRR formula may be unreasonably low. For instance, the PER for UL is only 23 times, yet the IRR's expected return is -11%, which is clearly an unreasonable figure.


針對上述問題,投資學課本教導我們採用二分法來處理:
當企業成長到某一階段後,轉為低成長。
然而這種做法過於主觀,
中期以後的成長率應調降至何種程度,不可知。
To address the above issue, investment textbooks teach us to use a binary approach:
if a company enters a low-growth phase after reaching a certain stage of development.
However, this approach is overly subjective,
as it is unclear how much the growth rate should be reduced in the mid to long term.
當 IRR算法出現不合理結果時,我主張改用本益比法,
以避免過多的人為主觀調整。
此方法不僅標準明確,而且普遍適用。
If the IRR formula yields unreasonable results, I suggest using the PER method instead to eliminate the drawbacks of subjective adjustments. The standards for using the PER method are clear and can be easily applied.
PER法:
我規定貴價本益比30倍之預期報酬率為0;
淑價預期報酬率15%
PER4倍漲到30倍,預期報酬率為(30/4)^(1/8 )-1=28.6%
淑價x(1+15%)^8=預期EPSx30
貴價x(1+0%)^8=預期EPSx30
PER method:
I stipulate that for pricey price the PER is 30 times and expected return is 0;
for cheap price expected return 15%
PER increases from 4 times to 30 times, expected return is (30/4)^(1/8 )-1=28.6%
cheap price x(1+15%)^8=expected EPSx30
pricey price x(1+0%)^8=expected EPSx30
換軌點:由 IRR法切換為PER法
在計算預期報酬率時,
當 IRR法淑價與貴價之平均數
高出或低於20%PER法時,
視為 IRR法偏離合理範圍,應改以PER法作為估值依據。
Change point: from IRR to PER method
We will switch from using the IRR method to the PER method for calculating expected returns when the average of the cheap and pricey prices obtained by the IRR method deviates more than 20% from that obtained by the PER method.
全市場真正依據 IRR公式進行股票買賣的,
恐怕只有我們巴菲特班。
盈再表包含了還原股價、ROE、常利、盈再率、配息率、IRR、PER 法與換軌點等多項指標,
看似平凡卻蘊藏了本人獨門秘訣。
雖然已將這些設定全數公開於盈再表中,
但我相信大多數人仍難以完全理解,因為相當複雜。
Across the entire market, the only ones who truly buy and sell stocks based on the IRR formula are probably just our Buffett class. On's table includes several indicators such as adjusted stock price, ROE, recurring profit, PR%, payout ratio, IRR, PER method, and change point. While these indicators may appear ordinary, each has its own secrets. On's table fully discloses how to set up these indicators, but they may be difficult for most people to comprehend due to their complexity.
總算講完了,本章是整個課程最多數學的地方,
有位同學不敢置信一個人在馬桶上
竟然可以想出這麼複雜的計算,
一直問我在馬桶上待了多久?
馬桶和蘋果樹都是人類文明的搖籃啊!
In conclusion, I have finished my speech for this section. The mathematical content covered here is the most complex in the entire course. One student couldn't believe that someone would sit on the toilet and contemplate such complicated calculations, and kept asking me how long I had been sitting there. However, toilets and apple trees are the cradles of human civilization! |