What are Upper and Lower Quartiles?
Other statistical parameters that may be reported in the media or in REIWA research from time to time include the upper and lower quartiles. These are derived in a similar way to calculating the median by placing all records for a period in value order and identifying the values that represent: • the top of the bottom 25% of the market the lower quartile, and • the bottom of the top 25% of the market the upper quartile. Use of quartiles and the relative movement in values of the quartiles between quarters or over the year help us to understand which part of the market is moving relative to the median. The lower quartile tells us that 25% of the market was priced at or below the lower quartile value whilst the upper quartile indicates the top 25% of the market was priced above the upper quartile. It follows then that the remaining part of the market between the two quartiles represents 50% of the market and includes the median value.
