It’s never a good sign to see the Nasdaq leading the rest of the market lower, which it did this week. A -3% plunge on Friday (and a -5% loss for the week) made it the weakest of the major market indexes. Heavy selling in software and internet stocks were especially troubling. So is its chart pattern. The weekly bars in the chart below show theNasdaq Composite bearing down on its January and August lows. On a closing basis, the Nasdaq is already at the lowest level in more than a year.