Essentially a batch of NDX stocks are purchased by a financial entity, then turned over to the folks who will issue the QQQ. the ratio between the 2 is already set. Those shares of NDX stocks are kept "off market". They are not available to trade until the QQQ stock is returned. Since the ratio of NDX stocks to QQQ is always the same, the value of the QQQ is derived from the NDX.
For my calculations, QQQ x 40.22 = NDX Seems to work out pretty close.
Sorry so slow:) I was BZ… If you create a watch list; I use Quote Tracker, with QQQ and ^NDX in it, for the most part, you will see they do not track exactly, i.e. %gain, %loss, on a minute by minute bases.
Since the QQQ is; “the basket stock” of the nas 100, it is constantly being adjusted based on the trading of it’s individual components, “nas 100”. That is the basics and I’m sure it’s more complex than that. Don’t quote me on this but believe the QQQ trails. That’s why the QQQ closing price does not settle until 15 min after the close?
I do not have the exact link but I think if digging were done an answer could be found here http://www.nasdaq-100.com
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