Mumbai has been ranked sixth among top ten global cities on the billionaire count with 28[14] and 46000 millionaires, with total wealth of around $960 billion[15][16] it is the richest Indian city and 12th richest city in the world.[17][18] and seventh in the list of "Top Ten Cities for Billionaires" by Forbes magazine (April 2008),[19] and first in terms of those billionaires' average wealth.[20] As of 2008[update], the Globalization and World Cities Study Group (GaWC) has ranked Mumbai as an "Alpha world city", third in its categories of Global cities.[21] Mumbai is the third most expensive office market in the world, and was ranked among the fastest cities in the country for business startup in 2009.[22]