Here's another index to keep an eye on.
Back in late 2000 and again in 2007, the S&P 500 got to a high level and then retreated. This has the appearance of a double top - and if the pattern forms completely, it suggests the markets will go lower.
Other averages don't show the pattern quite as clearly, so it is not definitive - but if the pattern completes, then it is more likely than not that we will see a drop of several hundred points. 450 is not impossible.
So, the question becomes - how does the pattern complete? At the link is an annotated chart. We do not want a Friday close below 762. I specify Friday because the chart uses weekly figures, so there is only one bar per week.
And, as always, the standard caveat applies - this is just my opinion, and it wouldn't be the first time I was wrong.
LINK