By the Numbers

September Bad for Stocks? Why It's Different This Time

September is usually the worst month for stocks. But this year, it's actually been good for the market.

NYSE Clerks 1957

With just one trading day left in the month (and the third quarter), the Dow Jones Industrial Average is up about 2.5 percent so far.

The Dow, in fact, is on track to have risen in 11 of the past 12 months (it fell 6 percent in May). The last time that happened was in 1959.

Most of the Dow's gains this month came in the the first two weeksas Wall Street anticipated the Federal Reserve's new bond-buying program, which was announced on Sept. 13.

September, in fact, has been kinder to stocks in recent years, with the Dow rising in five of the past seven Septembers.

This month's gain would cap a remarkable one-year run for the blue chip average. In fact, over the last 12 months, the Dow is up 2,500 points, or 23 percent.

The best-performing Dow stocks (on a percentage basis) during this time include Home Depot +80 percent, Walt Disney +72 percent, General Electric +45 percent, Bank of America +44 percent and Wal-Mart +43 percent.

One-third of the Dow’s 30 stocks make up almost two-thirds of the total gain over the last 12 months.

Here’s a look at the impact all of the Dow 30 stocks have had over the past year (since the close on 9/30/11).