Several U.S. retailers posted weaker-than-expected sales for November, getting the key holiday season off to a sluggish start as consumers worried about the economy and double-digit unemployment.

Eight of the 11 retailers that reported by early Thursday missed estimates, including Costco Wholesale Corp , Children's Place
, Walgreen Co and Hot Topic Inc , according to Thomson Reuters data.

Sales results include the day after Thanksgiving, known as Black Friday, when retailers offer rock-bottom prices to kick off the holiday shopping season.

Early data on weekend shopping from the U.S. Thanksgiving Day on November 26 through Sunday showed only a slight increase in retail sales from the comparable 2008 period, when consumers were hammered by a deepening recession and credit crisis.

As of Black Friday, analysts had forecast a 2.5 percent rise in November sales at stores open one year, according to Thomson Reuters data. But estimates have continued to shrink since the weekend, and as of Wednesday, analysts expected a 2.1 percent increase.

That would still be the best showing since April 2008, but compares with a 7.8 percent decline in 2008, the worst drop since Thomson Reuters began tracking data in 2000.

Even if sales are flat or rise modestly during the holiday season, analysts said retailers should report improved profits because they have cut inventories and pared back costs to avoid the huge discounts they were forced into last year.

Retail sales data are closely watched as consumer spending makes up roughly 70 percent of the U.S. economy. But the figures also give an incomplete picture because many of the retailers that are key holiday destinations, including industry leader Wal-Mart Stores Inc , Best Buy Cos Inc and Amazon.com , do not report monthly sales.

Costco said on Thursday that same-store sales rose 6 percent, missing the analysts' average estimate of 8.1 percent. Same-store sales at U.S. locations rose 2 percent.

Children's Place Retail Stores posted a 13 percent drop in comparable sales, including online sales, compared with analysts' expectations for a 1 percent rise.

Walgreen Co, one of the largest retailers that reports monthly same-store sales figures, on Wednesday posted a 3.9 percent rise for November, below analysts' expectations. The drugstore chain also said Thanksgiving weekend was notably softer.

Also on Wednesday, teen clothing retailer Hot Topic Inc posted a worse-than-expected 11.7 percent drop, while Aeropostale was slightly worse-than-expected with a 7 percent increase and a fourth-quarter forecast that disappointed some investors. Aeropostale shares were down 7 percent in thin premarket trading.

On the positive side, Limited Brands Inc , owner of Victoria's Secret and Bath & Body Works, posted a better-than-expected 3 percent increase,

Also, home furnishings retailer Pier 1 Imports Inc
cited a strong Thanksgiving weekend as it reported a 13.7 percent increase in same-store sales for its third quarter ended November 28.

(Reporting by Brad Dorfman; Editing by Lisa Von Ahn)