Calculating the university aggregate and ATAR
In South Australia or the Northern Territory, to obtain a university aggregate and an ATAR you must:
- qualify for the SACE/NTCET
- comply with the rules regarding precluded combinations
- comply with the rules regarding counting restrictions
- complete at least 90 credits of study in Tertiary Admissions Subjects (TAS) and Recognised Studies at Stage 2 in a maximum of three attempts which need not be in consecutive years
- of the 90 credits of study a minimum of 60 credits of study must be from 20 credit TAS*.
* Normally 10 credit subjects do not count towards this requirement but some 10 credit subjects in the same area, when studied in pairs, can substitute for a 20 credit subject. These are called valid pairs.
Calculating the university aggregate
The university aggregate is calculated from your best scaled scores from three 20 credit TAS plus the best outcome from the flexible option, which is the best 30 credits of scaled scores or scaled score equivalents from:
- the scaled score of a 20 credit TAS
- half the scaled score of one or more 20 credit TAS
- the scaled score of one or more 10 credit TAS
- scaled score equivalents for Recognised Studies to the value of 10 or the maximum of 20 credits
subject to precluded combination and counting restriction rules. Subjects with scaled scores of 0.0 can be used in the calculation of the university aggregate.
The subjects used in the calculation can only come from a maximum of three attempts which need not be in consecutive years. For example, if a student attempts study in the years 2011, 2012, 2015 and 2018, an aggregate will be calculated from each possible combination of three attempts as follows:
- 2011, 2012 and 2015
- 2011, 2012 and 2018
- 2011, 2015 and 2018
- 2012, 2015 and 2018
The student will receive the highest of these aggregates.
Please note that study attempts prior to 1993 (pre-SACE) cannot be counted because comparable scaled scores for subjects prior to 1993 are not available.
Converting the university aggregate to an ATAR
The university aggregate is converted to an ATAR. The ATAR is an indicator of how well a particular student has performed relative to other students. It is calculated as follows:
- The group of students who may qualify for a university aggregate in 2018 is called the 2018 cohort.
- For each university aggregate (in the range 0-90.00) obtained by the students in this cohort, the percentage of students who obtained that aggregate or better is calculated. This is known as calculating the percentile distribution.
- Each university aggregate in the range 0-90.00 now has a corresponding percentile rank in the range 0-100. For example, if an aggregate of 78.00 or better out of 90.00 has been obtained by the top 10% of the cohort, the aggregate of 78.00 will correspond to a percentile rank of 90.00 (100 – 10).
- To derive an ATAR from the university aggregate we need to look at where the students in the cohort sit compared to the entire population who are in the same age group.
- The 2018 cohort may differ from that of other years in that it may represent a smaller or larger percentage of the population who are in the same age group.
- The percentage from the given year is known as the participation rate. It is calculated using population statistics obtained from the Australian Bureau of Statistics and measuring these against the size of the cohort.
- The percentile rank is adjusted to take account of the participation rate and where the student sits relative to the entire population, and the result is the ATAR. For example, if a student has an ATAR of 95.00 it indicates that they have achieved as well as, or better than, 95% of the population. This process ensures the ATAR is comparable from year to year.
- When the calculations are completed, a student’s relative position on the ATAR range is unchanged from the student’s relative position on the university aggregate range.
- It is important to remember that the ATAR is a rank, not a score.
Reporting the university aggregate and ATAR
The university aggregate is reported to students on a score range of 0-90.00 with intervals of 0.1.
The ATAR is reported to students on a percentile scale, i.e. on a range 0-99.95 with intervals of 0.05.
The university aggregate and ATAR are reported only to students who qualify for the SACE or NTCET.
SACE/NTCET university aggregate to ATAR conversion
Each year SATAC publishes tables showing the relationship between the SACE/NTCET university aggregate and the ATAR. This provides an accurate record of how the ATAR was ascribed to candidates in each year.
Students, teachers and parents/caregivers should note that prior year information cannot be used accurately to predict ATARs for students in future years. Students in particular should be wary of any advice that purports to do so.
The relationship between the university aggregate and the ATAR changes every year, depending on the population of 16 – 20 year olds in South Australia and the Northern Territory. For example, in 2015 an aggregate of 80.0/90.0 was awarded an ATAR of 95.20. Yet in 2016, an aggregate of 80.0/90.0 was awarded an ATAR of 94.75. In addition, the scaling outcomes for individual subjects changes from year to year, so it is not possible to predict the scaled score outcomes of studies in any year based on predicted A+ to E- SACE/NTCET grades.
SATAC is aware that there are websites that claim to contain “ATAR calculators”. These do not accurately calculate ATARs for students.
Please select from the links below to download a copy of the university aggregate to ATAR conversion table. Please note, the conversion tables for the years prior to 2012 are not available online.