Investors pulled billions of dollars from the largest exchange-traded fund tracking the Nasdaq 100 in recent sessions, the latest indication that investors are looking to take profits from a group that’s led this year’s stock-market advance. The PowerShares QQQ Trust ETF QQQ, +0.22 saw outflows of $1 billion on Monday, its second straight session with billion-dollar-plus redemptions, as well as its third session of the past five with such a large retreat. The moves have brought its outflows over the past week to $3.76 billion. That’s by far the largest redemption seen in any ETF over the past week, according to FactSet data.via