Housing

Housing loan quartiles

About this topic

Housing loan quartiles group households with a mortgage into four evenly sized repayment bands so mortgage costs can be compared more objectively across areas and over time. They describe the relative repayment profile of mortgaged households rather than fixed dollar amounts.

This topic is useful because direct repayment values are affected by inflation, interest rates, and housing market cycles. The 2021 Census occurred during a period of unusually low interest rates, so quartile comparisons are more informative than raw repayment levels alone.

Interpretation notes

  • This is a derived repayment distribution for households with a mortgage, so quartiles show relative repayment position rather than fixed dollar bands.
  • Quartiles are more useful than raw repayment ranges for comparing areas or years affected by different interest-rate settings.
  • The 2021 distribution reflects a low-interest-rate period before the rate rises that began in May 2022.

Key insight

In 2021, the lowest mortgage-repayment quartile held the largest share among households with a mortgage in Koondoola, accounting for 43.9%.

Section overview

Housing loan quartiles

Koondoola - Households (Enumerated)

This table summarises housing loan quartiles for Koondoola in 2021 for persons, with comparison against Wanneroo (C) and change since 2016.

Housing loan quartiles snapshot

2021 distribution by category for Koondoola, with comparison markers for Wanneroo (C).

Koondoola
Wanneroo (C)

Lowest group

2021 count

190

% of total

43.9%

Change from 2016

-

Medium lowest

2021 count

148

% of total

34.2%

Change from 2016

-

Medium highest

2021 count

69

% of total

15.9%

Change from 2016

-

Highest group

2021 count

26

% of total

6.0%

Change from 2016

-

Data table

Housing loan quartiles for Koondoola. Housing loan quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).

Housing loan quartiles for Koondoola. Housing loan quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).
Housing loan quartiles for Koondoola. Housing loan quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).
Category20212016Change
Count%Wanneroo (C)%Count%Wanneroo (C)%Countpp
Lowest group19043.9%21.2%20845.0%19.3%--
Medium lowest14834.2%26.9%14130.5%25.8%--
Medium highest6915.9%29.8%8718.8%30.8%--
Highest group266.0%22.0%265.6%24.1%--
Total households with stated mortgage repayments433100.0%100.0%462100.0%100.0%--