PRACTICAL STOCK INVESTING

measuring performance

I’ve written before about how important it is for us as stock market investors to calculate and analyze the performance of our portfolios on a regular basis.

There are two related reasons for doing this:

1.  We want to identify what ideas/stocks are working for us in the portfolio and which ones aren’t.  Based on this, we decide where to take profits and where to stop the bleeding.

2.  We also want to learn about ourselves, and our strengths and weaknesses in decision-making.  This isn’t like training for the Olympics.  We don’t need to be perfect at everything.  But we want to at least be able to identify situations where we continually shoot ourselves in the foot–and just not do that anymore.

doing it now

On July 7th, the S&P 500 closed at 1353.  On October 3rd, it closed at 1099, for a decline of 18.8%.  On an intraday basis, from 7/7-10/4 the fall was 21%.

The markets appear to be stabilizing now, as politicians in Europe make noises about finally addressing the EU’s Greece/banking crisis.  It’s too soon to say for sure that the worst is over (although I suspect it is).  But whatever the case may be, it’s important to look at your portfolio after a decline of this magnitude and ask yourself how you fared.

how to do it

In all likelihood, you don’t have data from your brokerage account that tells you either what your portfolio as a whole, or any individual security in it, was worth on the beginning and end dates.  So the easiest way to proceed is to use a Google chart to compare the performance of the S&P 500 (or whatever benchmark you measure your portfolio against) with each of the stocks/mutual funds/ETFs you own.  You can find more details toward the end of my post on “method to the madness” a few days ago.

what to look for

1.  One question is whether you’ve outperformed or underperformed the benchmark. But that’s just the start.

2.  Growth investors outperform in up markets and underperform when the market is declining.  Value investors, who have a more defensive bent, do the opposite.  So a second question is whether your portfolio has performed in line with your design.

3.  Is your design really what you wanted?  Is it appropriate for your financial circumstances, or is it too risky–or not risky enough (not the usual problem, but possible)?

4.  What were your strongest and weakest stocks?

5.  Is there a pattern to either the good ideas or the bad ones?  Be careful here.  Over this period, utilities stocks would have been stellar names, capital goods or materials stocks were probably at the bottom of the pile.  That’s not what I mean. You’re looking for behavioral patterns that lead you astray so that you can change them.

Do the weak stock ideas come from names you hear on CNBC?  Are the good names ones where you know the financials backwards and forwards and the bad ones those you know less well?  Are the horrible stocks tips from cousin Fred the broker?  Are the large positions winners and the small positions losers–or the reverse (which would be a more serious issue)?

Some fixes are easy:  turn off the TV; do your homework; don’t act on Fred’s advice; don’t bother with the small positions (or weight each position equally if the small ones are good but the big ones are killing you).

6.  How are your positions doing in the rebound?  Stocks rarely outperform in both up and down markets.  Great if you have one or more of these.  In contrast, in my experience it’s a big red flag if a stock underperforms on the way down and remains an underperformer in a market bounce.  Any like these are ones that need your immediate attention.

7.  Are the reasons you bought each security still valid?

two other thoughts

–Looking at your portfolio decisions with a critical eye is something you need to do regularly.  One time won’t be enough to detect behavior patterns.  But you’ve got to start somewhere.  My experience is that even professionals make mistakes that would be easy to correct–like “don’t listen to Fred”–except that they aren’t aware they’re making them.

–For an analysis like this, don’t use year-to-date numbers.  What you want to see is how your stocks have done in the downturn.  Otherwise, if you have had significant under- or outperformance earlier in the year, that performance difference will just muddy the waters.  An example:

Suppose you have a security/portfolio that was 20 percentage points ahead of the S&P through July 7th.  That would mean you had a gain of 27.7%.  On October 3th, your holdings are down 2.7%, which is ten percentage points better than the market.  How much performance have you lost during the downturn?

The answer isn’t ten percentage points.  It’s five!  During the period we’re considering, the S&P 500 fell by 18.8%.  Your investment went from 127.7 to 97.3.  That’s a fall of 23.8%.  The difference between the fall in the index and in the investment is five percentage points.  The rest of the year-to-date loss comes from the fact that the investment has lost its 18.8% from a starting point that already incorporates a large year-to-date gain.  The gain portion also suffers a loss.