The 7 must-know numbers of the week

The amount by which the average net worth of the richest 20% of Australians increased since 2005-2006, according to the Australian Bureau of Statistics. During the same period the average net worth of the poorest 20% only increased by 4%.

The recent sale price of Bilabong Station, in rural New South Wales, which was passed in at auction but sold the next day. The sale marks a strong start to the spring selling season in rural areas, especiall the Riverina.

The amount by which Melbourne's median house price fell during the September quarter, according to the Real Estate Institute of Victoria. The results equated to more than two-thirds of Melbourne's homes having either lost value or stayed flat in price over the past three months, with just 78 of the 272 reported suburbs growing in value over that time.

The reported approximate price achieved  for Updown Court, the United Kingdom country estate whose saga highlights the European banking credit over-indulgence. It was initially priced at in excess of £70 million. The private lender, Irish Nationwide Building Society, had provided funding totalling about £63 million at the heyday of the credit boom. At one stage the building society even held a board meeting at the mansion.

The number of Sydney suburbs that recorded annual rent increases topping 10% for new tenancies during the September quarter. Most are in inner-Sydney, but Ryde is also among them.

The number of lenders that cut their fixed rates during October. The Commonwealth Bank has cut its fixed rates further than the other three major banks.

The highest auction sale price for the week, according to RP Data. It is for a rare 10,000-square-metre Warrawee offering sold by the Diocese of Broken Bay.