Austria has one of the densest millionaire populations in the world, a survey has revealed.Boston Consulting Groups (BCG) Global Wealth Report 2011 shows that, with 5.2 million households, most US dollar millionaires live in the United States of America. Millionaire households represented only 0.9 per cent of all households in the world. These families owned 39 per cent of global assets in 2010, up by two per cent to the year before. There were 12.5 millionaire households in the world last year, 12.2 per cent more than in 2009.The highest concentration of super-wealthy families was detected in Saudi Arabia. Eighteen of 100,000 households in Saudi Arabia have investable assets of 100 million US dollars or more. Switzerland is in second place (10 per 100,000), followed by Hong Kong (nine per 100,000) and Kuwait and Austria with eight per 100,000 households each. China experienced the fastest growth in the number of mega-rich families. The figure soared by more than 30 per cent from 2009 to 2010 to 393.The USA and China were ahead regarding the absolute gain in wealth last year, according to the BCGs report which was published yesterday (Tues). The largest wealth increase was recorded in the Asian-Pacific region at 17.1 per cent, far ahead of Europe (plus 4.8 per cent).BCG investigated 62 countries on all continents for its new report. Those states represent more than 98 per cent of the global gross domestic product (GDP), according to the internationally operating management consulting firm which was founded in 1963.BCGs data comes as political decision-makers in Austria are engaged in an intense discussion over introducing a new tax targeting the wealthiest residents of the country.The Social Democrats (SPÖ) have focused on promoting such ideas in past months. Poll results show that the party managed to avoid a substantial decline in popularity this way in contrast to its coalition partner, the conservative Peoples Party (ÖVP). The ÖVP expressed concerns whether a tax on assets would significantly increase tax revenue. The party also said such a levy would mean some of the richest Austrians would relocate their assets from Austria in favour of stashing them on accounts abroad and invest in real estate outside Austria.Only half a year ago, various tax increases agreed upon by the SPÖ-ÖVP coalition came into effect. Economists have said the government can expect more revenue than it initially expected in the coming years due to the quick recovery of the federal economy. However, SPÖ and ÖVP have also been urged to spend less on bureaucratic and administration means to reduce the climbing state debt.Investigations have shown that one million of Austrias 8.5 million people are at risk of becoming impoverished. Statistics also reveal that 10 per cent of Austrians own nearly 60 per cent of the countrys private assets. Six per cent of Austrians are categorised as poor by international standards, while the country ranks among the worlds 10 wealthiest nations and among the Eurozones top five.The Piech & Porsche family are listed as the richest Austrians in various rankings with estimated assets of 28.6 billion Euros. The heirs of German-Austrian industrial business family Flick are in second place (5.7 billion Euros). Red Bull founder and boss Dietrich Mateschitz and Karl Wlaschek a bar pianist who went on to set up supermarket chain Billa are neck and neck in third with around four billion Euros each.Andreas Treichl is listed as the top-earning head of an Austrian company. The Erste Group Bank AG (Erste Bank) raked in 2.79 million Euros last year. Strabag SE boss Hans Peter Haselsteiner is second with an annual income of more than 2.5 million Euros.