Won't change it at all. It will just get a new divisor so the initial number will be exactly the same. Of course the new stocks will trade differently, and IMO will throw off support/resistance areas. And yet .... there is an interlocking of the markets. The DJIA and SPX tend to track each other fairly closely. In my research into the inner workings of the markets, there are those that actually play the spread. They for instantance go long the DJIA and short the SPX to make money as the spread changes. Currently there is about a 95% corrolation between the two. So in reality there probably won't be all that much difference. And looking at the charts between the tossed and the added, I don't see all that much difference.