While mechanical servants aren’t yet available at Wal-Mart, a United Nations report says automated, intelligent household robots will become common in the next five years.

According to the World 2002 Robotics Report by the UN Economic Commission for Europe, there were 21,500 domestic robots sold in 2001. Between 2002 and 2005, says the report, that number should hit 700,000.

The reason: Technological improvements and falling prices. Automated vacuum cleaners hit the market in 2001 for about 1,400 euros. But new models have recently come out at far lower prices.

“Prices are going to come down just as they did for personal computers,” Jan Karlson, a UNECE expert who helped produce the report, told Reuters. “When PCs started to be used by private people, they were pretty expensive.”

UNECE also predicts that industrial robots will become more widespread by 2005. At the end of 2001 there wre 760,000 industrial robots. By 2005 this should rise to 965,000.

Growing numbers of robots could help address the problem of declining work forces, notes the report.