Dear shebonline, I found your use of statistics a quiet interesting art form. Trying to create something that isnt there.
I did a little research, not much, and found the following defintion of 'unoccupied' from the ABS web site. If you read the definition, it is the number of unoccupied houses that the Census collector visited, not the number of houses were there are no people living or are avaialble for rent as you seem to be implying. Actually, for the last census I was away from home.
And bubblepedia is your authoirty. Come on, as they say there a lies, damn lies and there statistics.
ABS defintion of Dwelling
In general terms, a dwelling is a structure which is intended to have people live in it, and which is habitable on Census Night. Some examples of dwellings are houses, motels, flats, caravans, prisons, tents, humpies and houseboats.
Private dwellings are enumerated using Household Forms, which obtain family and relationship data. Non-private dwellings (hotels, hospitals etc.) are enumerated on Personal Forms.
All occupied dwellings are counted in the Census. Unoccupied private dwellings are also counted with the exception of unoccupied dwellings in caravan parks, marinas and manufactured home estates, and units in accommodation for the retired or aged (self-care). Unoccupied residences of owners, managers or caretakers of such establishments are counted
