Driving the trend is Western Australia, where the average new mortgage rose to $319,000 - a 35% rise over the past year. AFG, the nation's largest mortgage broker, also recorded its biggest ever proportion of mortgages advanced to investors in WA, where 48% of new loans were for investment purposes. Queensland figures also showed strong increases, with the average mortgage in that state sitting on $297,000, up from $243,000 in May 05. Other states showed less dramatic increases, with NSW shifting from $367,000 in May 05 to $371,000 in May 06. Victoria showed an upward trend from $248,000 last year to the current figure of $276,000. The report also showed that for the first time, more than 20% of new borrowers are choosing fixed interest rate mortgages. This trend is not surprising as borrowers brace themselves against possible future rate hikes. Overall, however, it appears that May's interest rate rise has had little impact on the nation's mortgage market. "We had our best month ever in May, so there's no sign at all that the rate rise has had an impact on our business," said Malcolm Watkins, executive director of AFG. "While the $300,000 may not be a definitive figure, it's strongly indicative of what the market is doing, especially with the continuing resource boom driving WA."