New mortgage lending to property investors spiked up in May, while lending to owner-occupiers fell.According to the latest Australian Bureau of Statistics housing finance data, the value of new mortgage lending to residential property investors rose 3.9 per cent in May, compared with the previous month (in seasonally adjusted terms).The seasonally adjusted figures for investor lending have been volatile this year: down five per cent in April, up 1.5 per cent in March, up 4.1 per cent in February and down 1.6 per cent in January.According to Reserve Bank figures published at the end of last month, growth in investor housing loan balances continues to decline, falling from an annual growth rate of 6.5 per cent in April to six per cent in May.ABS figures show that the value of new lending to owner-occupiers fell 0.6 per cent in May, compared with the previous month.Overall, the value of new lending rose one per cent in May. Total new lending of A32.3 billion was three per cent higher than the same period last year.The average loan size was A$357,300 - down from $361,500 in April.