How Much Does IBM Stock Move When The Market Moves?

International Business Machines (IBM) has risen 6.0% over the last five trading days while the S&P 500 fell 1.3%. A run like that in a weak market pulls money in, but the five-day move is not the question worth answering. What matters is what IBM does to your money when the market moves. Most of what IBM does has little to do with the market.

IBM Has Taken More Of The Bad Days Than The Good

On days the S&P 500 rose over the past year, IBM captured about 83% of the gain. On days the index fell, IBM took about 102% of the loss. That is a one-year reading of daily moves. For investors evaluating a recent breakout, an asymmetric downside capture ratio warrants closer inspection.

IBM is not a quiet stock. Over the past five years it ran 30.3% annualized volatility against 17.2% for the S&P 500. Its daily moves have tracked the index with a correlation of only 0.36 across those five years, so most of that movement is IBM’s own. Independence like that comes from what…