There are 8.6 million robots in the world -- or more than one automaton for every person in Austria.I arrived at the 8.6 million estimate based on data from the latest edition of World Robotics, a great numbers-filled report prepared annually by good folks at the International Federation of Robotics, or IFR. The report came out late last year -- I finally had time to take a look at it -- and refers to the robot market up to the end of 2008.So how are robots doing compared to previous years?As you can see from the chart above, the number of industrial robots grew to 1.3 million in 2008 from about 1 million in 2007, and service robots grew to 7.3 million from 5.5 million. So for industrial and service robots combined it's a 32 percent increase from 2007 to 2008, and that's huge.That said, you have to understand the numbers. The World Robotics report doesn't add up industrial and service robots. I do. The report keeps these two categories separate, I believe, because these are very different robots in terms of complexity and cost: an industrial robot can be a multimillion dollar manipulator whereas a service robot can be a $50 dollar toy robot.Another reason to keep them separate: the total numbers for each category mean different things. The total of industrial robots is for "'worldwide operational stock," or robots actually operational today. On the other hand, the total of service robots consists of units sold up to the end 2008, which includes robots no longer in operation like that first-generation Roomba you harvested for parts long ago.So why do I add the numbers? Well, because I think it's cool to have a number for the world's robot population.Now on to some highlights from the report and in particular, industrial robots.• According to the report, 2008 sales reached 113,000 units, which is about the same as the previous year. It's a weak result, and the culprit, as you might have guessed, is the global economic meltdown.• A breakdown by region. Of the 2008 robot sales, more than half, or about 60,300 units, went to Asian countries (including Australia and New Zealand). The world's largest market, Japan, continues to see a decline, with supply falling by 8 percent to about 33,100 units. But Korea and emerging markets like China and the Southeast Asian countries and India saw increases in sales, with Korea adding 11,600 robots, up 28 percent from 2007, China adding 7,900 units, an increase of 20 percent, and Taiwan's robot acquisitions surging by 40 percent.• In the Americas, the robot market grew by 17,200 units, or 12 percent less than in 2007. Auto industry, the main robot buyer, retreated and robot sales plunged.• Robot sales in Europe stagnated at about 35,100 units, with Germany taking the lead, adding 15,200 robots, 4 percent more than in 2007. Italy, Europe's second largest market after Germany, added 4,800 units and France, 2,600 robots.• So the total of industrial robots in 2008? First, a number that I hadn't seen before. The report says that "total accumulated yearly sales, measured since the introduction of industrial robots in industry at the end of 1960s, amounted to more than 1,970,000 units at the end of 2008." That's basically the total of industrial robots sold in the world. Ever. Cool! So to get the total of industrial robots in operation you need to remove the ones that have been taken out of service. People use different statistical models to do that, arriving at different numbers. The World Robotics report gives an estimate between 1,036,000 and 1,300,000 units.• Still according to the report, world industrial robot sales amounted to about US $6.2 billion in 2008. But this amount doesn't include cost of software, peripherals, and system If you were to add that up, the market would be some three times larger, or around $19 billion.