The Associated Press

NEW YORK — U.S. retail sales of video game systems, software and accessories slipped 1 percent in July according to market researcher

A lackluster summer game launch schedule partly offset strong sales of the Xbox 360.

Total industry sales slid to $846.5 million last month from $850.6 million in the same month a year earlier.

But when counting “StarCraft II,” which is excluded from these figures because it’s a PC game, total industry sales actually grew 4 percent, according to NPD analyst Anita Frazier.

“StarCraft II” sold more than 1.5 million units worldwide in its first 48 hours in stores according to its publisher, Activision Blizzard Inc. NPD does not include the game in its monthly game sales data because it counts PC games separately.

NPD said hardware sales jumped 12 percent to $313.8 million in July. The Xbox 360 from Microsoft Corp. was the month’s best-selling gaming system, thanks to the popularity of its new, slim format. Frazier said this was the first time since September 2007, when “Halo 3” launched, that the Xbox 360 was the top-selling gaming platform.

Both the Xbox 360 and Sony Corp.’s PlayStation 3 sold more units than expected, said Jesse Divnich, an analyst with Electronic Entertainment Design and Research. It’s likely a sign customers are buying second, or even third consoles as they migrate from the Wii to the more powerful gaming systems.

Even so, Divnich added the Wii will be a strong seller over the holidays, as it has been since it launched nearly four years ago. Earlier this week, Nintendo said the Wii has sold 30 million units in the U.S., reaching the milestone faster than any other gaming console.

July’s software sales, meanwhile, fell 8 percent to $531.3 million, not including “StarCraft II.” Of the console games, “NCAA Football 11” from Electronic Arts Inc. was July’s top selling title.

Sales of video game accessories slid 2 percent to $129.3 million. For the fifth month in a row, the best-selling accessory was the Xbox Live 1600 point card. The card, which costs $20, lets users pay for movies, games or extra game content through their Xbox 360 systems. The success of such cards “points to the activity that is happening in the industry outside the traditional retail channel,” Frazier said.

Total industry sales for the year through the end of July were down 8 percent to $7.51 billion.

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