Although you still don't have to declare domestic robots on your council tax return, the IFR Statistical Department supported by the robotics and automation division of the VDMA, the German mechanical engineering and plant manufacturing association, carries out an annual check on how many of them are running around on the earth's surface and what they are doing there.

The summary in the IFR World Robotics 2008 report, just out, says they are everywhere. At the end of 2007, around one million industrial robots and 5.5 million service robots were working around the world: in factories, in dangerous and unhealthy environments, in hospitals, in private households, in public buildings, underwater, under the earth, in fields, in the air, and in space. By the end of 2011, this number is expected to rise markedly. According to the IFR estimate, based on an assumed four per cent worldwide growth in each of the coming years, 1.2 million industrial robots and 17 million service robots will then be populating the world.

Almost 115,000 industrial robots were newly added in 2007. Turnover last year on the worldwide market for robotic systems - which includes hardware, software, peripheral devices, and industrial systems development - was approximately $18B. For comparison: the total IT turnover worldwide in 2007 was about 915 billion euros, according to estimates by EITO, a European market research institute specializing in IT.

As these figures already suggest, robots are not yet quite so omnipresent in industry as computers. The IFR says that in Japan, the country with the highest density of robots in the world, there are currently 310 industrial robots compared to 10,000 human employees in the processing industry. In Germany there are 234, in South Korea 185, 116 each in Italy and the USA, and in Sweden 115, while in all other countries examined there are fewer than 100 robots per 10,000 workers. But in the Japanese motor industry, a leader in automation, a ratio of one robot to just five workers has already been reached.

But the IFR concludes that the crucial contribution to growth in the robotics industry is no longer being made by Japan, and even its motor industry, hitherto the main customer, has not been driving the market on its own for some time. The worldwide trend toward automation in other industrial fields, such as metal, food and beverages, glass, pharmaceuticals, medical technology and photovoltaics, has been particularly strong in 2007, says the IFR.

The report has not until now covered the use of automated helpers in non-industrial domains in quite so much detail as the long investigated industrial field. So the Executive Summary of the IFR report (PDF file) only shows that in late 2007 a total of 49,000 service robots, with a value of around $7.8B, were installed for professional use. Of these, 25 per cent were service robots for defence, rescue and security, 20 per cent were agricultural robots (mainly milking robots), 12 per cent each were cleaning robots and underwater systems, 9 per cent construction and demolition robots, 9 per cent were medical robots and 7.4 per cent were mobile platforms for various fields of application, as well as some logistical systems, inspection systems, and public relations robots.

Private use of robots is not yet increasing as much as in industry, but still, in 2007 use of personal service robots increased by approximately one million to a total of 3.4 million: vacuum cleaners, floor cleaning machines and lawnmowers, as well as two million robots used for entertainment, as toys or for training, or were bought by hobbyists.

But although the current market is still very small, in view of demographic developments and increasing technological progress, the IFR report predicts that robots for assisting elderly and handicapped persons will develop into a key segment among service robots in the next ten years.