The Housing Industry Association (HIA)/Commonwealth Bank Housing Affordability Index revealed affordability has dropped by 5.5% to 97.9 over the December quarter last year. This is the first time the index fell below the 100 mark since the measure was introduced in 1984. Over the last 12 months, affordability tumbled 15.5% as the full impact of three rate rises begins to bite. An average first homebuyer now needs more than a third (30.7%) of their disposable income to service their mortgage - an increase of 1.7% compared to the September quarter. The monthly loan repayment needed on a typical home loan jumped by 6.3% to $2,332. Affordability dropped across all metropolitan areas with ACT suffering the biggest decline. Affordability in the capital tumbled 7.9% amidst skyrocketing home prices. Sydney suffered a 4.7% decline while affordability in boomtown Perth fell 7.4% to 82.7, making the western city the least affordable in Australia. The Housing Industry Association blames the rising interest rates and crippling shortage of available housing for the sharp decline in housing affordability across the country. "It's patently obvious that the correction in housing markets and subsequent improvement in affordability predicted is way off the mark," says Simon Tennent, HIA executive director of housing and economics. "The combination of rising prices over the quarter and the triple whammy of higher interest rates have pushed housing out of reach for an increasing number of households, who are already facing sharp increases in private rents," he adds.