最近在重讀巴菲特的年報，看到1978年的年報中，有一段描述Berkshire的紡織業，雖然不多，但這些話可以學到某些判斷一家企業好壞的重要因素：
Earnings of $1.3 million in 1978, while
much improved from 1977, still represent a low return on the $17 million of
capital employed in this business. Textile plant and equipment are on the books
for a very small fraction of what it would cost to replace such equipment
today. And, despite the age of the equipment, much of it is functionally
similar to new equipment being installed by the industry. But despite this
bargain cost of fixed assets, capital turnover is relatively low reflecting
required high investment levels in receivables and inventory compared to sales.
Slow capital turnover, coupled with low profit margins on sales, inevitably
produces inadequate returns on capital. Obvious approaches to improved profit
margins involve differentiation of product, lowered manufacturing costs through
more efficient equipment or better utilization of people, redirection toward
fabrics enjoying stronger market trends, etc. Our management is diligent in
pursuing such objectives. The problem, of course, is that our competitors are
just asdiligently doing the same thing.
The textile industry illustrates in
textbook style how producers of relatively undifferentiated goods in capital
intensive businesses must earn inadequate returns except under conditions of
tight supply or real shortage. As long as excess productive capacity exists,
prices tend to reflect direct operating costs rather than capital employed.
Such a supply-excess condition appears likely to prevail most of the time in
the textile industry, and our expectations are for profits of relatively modest
amounts in relation to capital.
這兩段我覺得有很重要的重點，是企業的資本運用，巴菲特很強調的衡量一家企業或是管理階層的好壞，是投入資本的報酬率，而非成長率的高低，在1977年的年報當中，他有說
Most companies define record earnings as a
new high in earnings per share. Since businesses customarily add from year to
year to their equity base, we find nothing particularly noteworthy in a
management performance combining, say, a 10% increase in equity capital and a
5% increase in earnings per share. After all, even a totally dormant savings account
will produce steadily rising interest earnings each year because of
compounding.
通常ROI越高的企業，都會有獨特的競爭優勢，讓他們得以享有高的資本報酬率，而資本報酬率還可以細部的拆解，去理解一家企業他的資本運用強項到底在哪，在這邊巴菲特有提到這一點，而這觀念很像是杜邦公式。
企業的資本運用，主要會是資本支出，營運資本與購併活動，這也是巴菲特在capital
turnover所提到的兩個重要項目，fixed asset以及investment in receivables and inventories，即使買進的固定成本低，但因為需要大幅花費在營運資本上，加上margin低，使得資本報酬率低，這也可以得知，資本報酬率，是由資本周轉率與margin所組成，而資本周轉率，主要是看固定資產與營運資本周轉率。
而一家企業，要提高它的資本報酬率，除了提高margin以及周轉率之外，另一個方法就是降低分母-資本，也就是多餘不用的資本，可以用發放股利或是share buyback的方式降低資本。
由以上，我們可以知道，margin高，不一定ROCI就高，margin跟周轉率高，也不代表ROCI高，因為你所花的資本可能也很多，或者是保留太多的資本在公司。
這邊我舉三家公司的例子來看，Apple，IBM以及Herbalife(HLF)，儘管HLF最近的議題，但他的財務數字真的很棒，所以我還是拿來做一下比較。
三家都是ROCI很高的公司，以過去五個年度平均來看，都超過25%：
AAPL: 29.48%
HLF: 41.12%
IBM: 30.86%
很意外的是，AAPL不是最高，而且是一直以來都是相對較低的，雖然它的Net margin是最高
AAPL: 21.2%
HLF: 9.9%
IBM: 13.2%
很意外的是，HLF margin最低，卻有最高的ROCI，在來我們看一下Asset turnover，可以稍微代表capital turnover
AAPL: 1.05
HLF: 2.23
IBM: 0.9
可以看出HLF想有較高的ROCI是在於他有高於兩倍以上的資本周轉率，而IBM很低，再來看一些資本周轉率的細項：
Receivable Inventory Payable Fixed Assets Cash Cycle
AAPL 10.29 107.94 4.45 15.73 -35.34
HLF 36.03 2.98 11.29 16.31 100.25
IBM 3.62 19.41 6.55 7.04 64.01
HLF的應收周轉率特別高，這跟他的business model有關，而且固定資產的周轉率也高，
最後的問題是，既然AAPL的margin跟資本周轉率都比IBM高，HLF雖然有最好的資本周轉率，但其margin是最低，簡單說，其實高margin，資本周轉率不低，現金轉換能力強的AAPL，營運能力很好，但為何ROCI卻是最低？問題就在於AAPL不給股利也不做buyback，這邊看一下total payout ratio，就是cash dividend加buyback，除以net income
AAPL: 1.7%
HLF: 79.6%
IBM: 125.3%
過去五年的資本成長率
AAPL: 756.9%
HLF: 42.8%
IBM: 17.7%
由此可見，AAPL持有太多的剩餘資本在帳面上了，也就是AAPL是unfriendly to shareholders，這也跟賈伯斯的主張有關，但實際上太多的現金拉低了AAPL的ROCI，而太多的現金目前來看沒有促成更多的創新，儘管其營運面是很好的，但卻對股東很不好。
而ROCI絕對高低只是其中的一面，其趨勢也很重要，持續往上是最好，至少也要維持在一定的水位，這就表示公司或是管理階層在資本運用跟企業營運上市有非常好的表現，像IBM這種的公司，也值得長期投資。
