New Zealand's median house price rose an annual 6.7 per cent in May, with four regions recording new records, although activity slowed, according to the Real Estate Institute.

The national median house price increased to $540,000 in May from $506,100 in May last year, the institute said. It was unchanged from April. Sales volumes fell 18 per cent compared with a year ago, and the median number of days it took to sell a home increased to 37…