Broker writes fewer big bank loans 25 January 2013 5:07PM John Kavanagh The major banks' share of loans written by one of the country's biggest broker groups fell during 2012. Aggregator AFG, which claims a 10 per cent share of the mortgage market, released its 2012 competition index yesterday. It showed big banks' share falling from 79 per cent in January to 77.4 per cent in December.Big banks' share of investor loans fell from 84.8 per cent to 79.8 per cent, and their share of the refinancing market fell from 77.2 per cent to 73.2 per cent.Running against the trend, big banks' share of first-home buyer loans rose from 72.5 per cent to 77.5 per cent (AFG counts major bank subsidiaries, such as Bankwest and St George, as being part of the big banks' share).Not all the big banks lost share, however. AFG loan writers did more business with Commonwealth Bank and Westpac but less with ANZ and NAB.Among the smaller lenders, AFG did more business with Macquarie Bank (which doubled its share of AFG's business during 2012), ING Direct and ME Bank.Suncorp, Citibank and AMP Bank did less business with AFG through the year.Commonwealth Bank and its subsidiary, Bankwest, had a dominant position in the first-home buyer market, accounting for 38.9 per cent of AFG's business in December.