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Stocks kicked off December with a whimper as investors reacted to disappointing retail sales over the Black Friday weekend. The Dow Jones Industrial Average (DJINDICES:^DJI) finished the day down 78 points, or 0.5%, while the S&P 500 fell 0.3%. In the biggest shopping weekend of the year, consumers actually spent less than a year ago, the first time Black Friday weekend spending had fallen since at least 2006, confirming fears retailers had communicated in recent earnings reports. Retail stocks were down nearly across the board, as Target and Macy's both fell nearly 2%.

It wasn't all bad news, though. The Institute of Supply Management's manufacturing index hit its highest level in more than two years, reaching 57.3, up from 56.4, and ahead of expectations at 55.5. The gains were led by an increase an export orders, reflecting an improving economy in Europe and elsewhere overseas.

Krispy Kreme Doughnuts (NYSE:KKD) shares were looking burned today, falling 3.3% during the day and another 13.8% after hours after it issued poor guidance in its Q3 report. The doughnut chain actually had a strong quarter, delivering earnings per share of $0.16, a penny better than estimates, while sales grew 6.6% to $114.2 million, in line with expectations. Same-store sales grew 3.7%, the 20th consecutive quarterly increase. CEO James Morgan was happy with the quarter, saying, "We are pleased to have increased our top line at a healthy pace despite the tepid consumer spending environment." However, 2015 EPS guidance was below expectations at $0.71-$0.76, in part because of continuing negative comparable sales in international markets. Analysts had expected $0.77. With a P/E above 40 before the report, the drop shouldn't come as a surprise.

Elsewhere, (NASDAQ:AMZN) made headlines with reports that it was testing delivery drones. The pilotless helicopters could cut delivery times to as short as 30 minutes, CEO Jeff Bezos said in an interview on 60 Minutes last night. While Bezos admitted that the new technology was still years away, the drones are representative of innovative thinking that has been Amazon such a powerful force in the market despite minimal profits. Amazon shares were up more than 1% this morning, nearly cracking $400, before closing down 0.3%. The breakthrough technology would also need to clear several regulatory hurdles before coming into practice.

Fool contributor Jeremy Bowman has no position in any stocks mentioned. The Motley Fool recommends and owns shares of Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.