Tightened bank lending regulations and a cooling property market have combined to produce the biggest dip in average Australian home loan sizes in more than 15 years.

The size of the national average home loan declined by 7.71 per cent to $357,200 over the three months to February 29, according to consumer advocacy website finder.com.au. This includes a fall of more than four per cent in February alone. Loan sizes fell in every surveyed state and territory,…