A.1 Guide to interpreting figures and tables in this report

Average

The average is calculated by summing all values and dividing by the total number of values. This is also known as arithmetical average and mean.

Median and weighted median

The median value is the midpoint of all values. It is the point for which 50% of values are below and 50% of values are above.

In some cases a weighted median is quoted. This is an adjusted midpoint taking into account the number of employees at each classification level. The larger the population of a classification the greater impact it will have on the overall weighted median.

ighted median is an historical measure from successive APS remuneration reports. ‘Weighted median’ is labelled throughout this report where relevant.

Percentiles, quartiles and box plots

This report uses box plots to visualise the position of the 5th, 25th, 50th, 75th and 95th percentiles for Base Salary, Total Remuneration Package (TRP) and Total Reward (TR).

Percentiles mark intervals where data occurs, in relation to the whole dataset. Note that the 25th and 75th percentiles are referred to as Q1 and Q3 respectively. These intervals are described in the table below.

Table A.1 Percentiles used in this report

Example box plot elements

Figure A.1 shows box plots of base salaries paid to employees at a given classification level in two consecutive years. The horizontal axis shows the years, A (left column) and B (right column) and the vertical axis represents the amount of money paid.

In each set of 4 boxes (one set for each year), the percentiles are represented by horizontal lines and are labelled at their appropriate positions for P5, Q1, Q3 and P95. The median is represented by the thicker middle line.

The box colours are different to distinguish between intervals and focus your eye on the spread of data from the first to third quartile (Q1 to Q3), where the majority of data lies. They have no other meaning.

A larger box between percentiles indicates a greater range of data points between the largest and smallest values in that interval, in this case, base salaries paid. A smaller box indicates a smaller range of data points.

Therefore, in year B, the pay range increased at Q3—shown by larger distances between the median and Q3 relative to year A. In addition, there was no change in the 5th percentile, Q1 and median from year A to year B.

Figure A.1 Example box plots

Additional notes on interpreting this report

• Some columns in the tables may not add up because TRP and TR are calculated separately for each employee. These are the values that determine the median. Therefore median TR is not always the sum of all medians for Base Salary, TRP and TR.
• Data from this report should not be used to calculate past or present populations of the APS. For accurate data as at 31 December 2020, please refer to the 31 December 2020 Employment Data Release, which is available from the APSC website: https://www.apsc.gov.au/employment-data/aps-employment-data-31-december-2020-release
• Data is analysed and tabulated using several different propriety software packages which may lead to minor variances in data reported between tables. These differences are also evident when trying to recalculate values based on the data in the reports in common programs like Microsoft Excel.
• Changes in software used to analyse and produce the APS Remuneration Report occurred in 2017, from SAS to Tableau. This has resulted in minor changes to how the reported distribution data is calculated due to the two programs using different, patented methods for calculating percentiles when even numbers of observations occur. Such differences in calculations have had a minor impact on the position of percentiles that were reported in previous years.
• Therefore it should be noted that the data reported for previous years as presented in the current edition of the APS Remuneration Report will differ from reports published prior to 2017.
• Population data used for analysis in this report is based on data from the Remuneration Survey unless stated otherwise. This may differ from APS Employment Database data due to a different collection scope.