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Welsh Pupil Level Annual Schools Census and Pupil Attainment dataset

Welsh Pupil Level Annual Schools Census and Pupil Attainment dataset


Dataset summary

Full title of dataset: Welsh Pupil Level Annual Schools Census and Pupil Attainment dataset.

Period covered: From 2004 onwards.

Frequency of release: PLASC data are collected annually from schools in January.  The Pupil Attainment data are collected annually from schools in June for Foundation Phase (formerly known as Key Stage 1) , Key Stages 2 to 3 and from awarding organisations for Key Stage 4 and above in August of each year.

Geography: Wales.

Data updated: Annually.

Format output: Data are normally provided in Access database or CSV format.  Other formats may be available on request.

Size: Approximately 0.475 million records each academic year.

Data quality: Expected to be of high quality, see specific section for more information.

Example variables: Pupil characteristics: date of birth,  ethnicity, age, free school meals status, special education needs status, postcode, Foundation and Key Stage assessment, GCSE and A level or equivalent results.

Access: Yes, via application to the Welsh Government School Statistics team.

Documentation: Available from the Welsh Government website please click here.  Please also refer to the Welsh Government PDF pack for further information on this dataset.

Contact Details: General and application enquiries should be directed to the Welsh Government School Statistics team on:  or telephone 029 2082 5060.


Pupil Level Annual School Census (PLASC) and Pupil Attainment data have been collected annually from all maintained sector primary, secondary, and special schools in Wales since 2004.  Statutory requirements govern the returns made by schools.  Before 2004 data on pupil enrolments and attainment were collected at school level only. 

Prior to 2008, the census and attainment data were collectively referred to as the National Pupil Database (NPD) which was maintained by the Local Government Data Unit for Wales (not to be confused with the English NPD, which is run by the Department for Education).  Following a review of the NPD, the management of schools data was transferred to the Welsh Government School Statistics team.  Both the PLASC and Pupil Attainment datasets are now referred to separately, although they are still linked at the individual level using a Unique Pupil Number, as was the case with the NPD. Whilst the PLASC and Pupil Attainment datasets could be used independently, they are more valuable as a merged dataset in order to combine information on pupil characteristics with attainment results.

Each school maintains electronic records on their pupils throughout the year using a Management Information System.  Returns are made via a secure online data transfer system managed by the Welsh Government.  

The PLASC data contain approximately 0.475 million records for each academic year and include variables on pupil characteristics including date of birth, gender, home postcode, special education need status and free school meal status.

Data on the results of pupils’ Foundation Phase and Key Stage attainment tests are collected from schools during a separate exercise, usually carried out in June. Foundation Phase and Key Stage tests are taken at four different age points during compulsory education, typically at ages 7, 11, 14 and 16. In Wales, Foundation Phase, Key Stage 2 and Key Stage 3 are now examined by teacher assessment only.  Key Stage 4 relates to attainment in GCSE and equivalent qualifications.

The Welsh Government website contains information on PLASC and Pupil Attainment data as well as other data collected from schools including absenteeism rates, teacher assessments of non-core subjects and information on teachers (note that these datasets may not be at an individual level).  Statistical release documents are also available to download and some aggregated data in the form of Excel spreadsheets are also available.  For more information visit: searching under topics for ‘Statistics’ or ‘Education and skills’.

StatsWales is run by the Welsh Government and provides access to a range of government data including data on schools and teachers.  Data tables are available to download for free in .csv and .xls format from their website (  Some of the data are available across a time series dating back to 1977/78, and there is a further section on historical data containing data collected prior to 1974.  The data are presented as aggregated totals limiting its use as a resource for detailed analysis.

Raw individual level PLASC and Pupil Attainment data can be made available to researchers via application to the Welsh Government’s School Statistics team.  Applications are dealt with on a case-by-case basis and will be subject to a data sharing agreement.  More information is contained in the ‘Access’ section below.


The PLASC and Pupil Attainment dataset covers pupil and school level data for all maintained primary, secondary, nursery and special schools in Wales.  England, Scotland and Northern Ireland have separate systems.

From 2004, PLASC and Pupil Attainment data have been collected from schools at an individual pupil level and in a standardised computerised form.  Previously data were collected at school level only. 

Data updates
PLASC data from the previous collection can be made available to researchers after official publication of the statistics, usually in the following July.  For Pupil Attainment data, Foundation Phase and Key Stage 2-3 data are made available in August, and Key Stage 4 data in November.  Fully matched PLASC and Pupil Attainment datasets are normally available the following January.  To download the latest reports visit:

For further information on PLASC dataset releases download our administrative data timetable here.  You can also follow the ADLS on Twitter to receive information about when new PLASC releases are available.


Examples of usage
Both the PLASC and Pupil Attainment datasets are a key source of education statistical analysis used by the Welsh Government and are published as Official Statistics.  For example, yearly reports are published on National Curriculum assessments and GCSE attainment, class sizes, absenteeism rates and other topics (see:  It is particularly useful for schools and local authorities for comparisons and benchmarking purposes.

Other key users include the Ministers and the Members Research Service in the National Assembly for Wales, Her Majesty’s Inspectorate of Education and Training in Wales, Wales Audit Office, the Department for Children, Education, Lifelong Learning and Skills in the Welsh Assembly Government, local authorities and the Department for Education in England.

The Welsh Index of Multiple Deprivation (WIMD) provides a good example of a research project which uses pupil level data.  Using data from a linked dataset of PLASC and Pupil Attainment, the WIMD contains indicators of Key Stages 2, 3 and 4 average point scores and primary and secondary school absence rates.  The home postcode information collected in PLASC enables the indicators to be constructed at a small area level (Lower layer Super Output Area). For more information see:

Publications using this research data are available from our Publication Hub here.

Technical guidance
It is important for researchers to take into consideration any changes to the data collection over time and how these changes affect the comparability of data from subsequent years. 

In line with the requirements of the data holders and attempts to improve the quality of the data there have been various changes made to the variables collected in PLASC.  Recently the coding of a pupil’s ethnicity has been extended to cover a series of sub-categories not previously available.  Another recent change is the introduction of more detailed categories of English as an Additional Language to provide information about the level of English speaking acquired by the pupil.

The guidance notes issued to schools to aid in their completion of PLASC provide a full overview of the variables currently collected and further details of recent amendments.  These can be accessed from:

The School Statistics team will be able to provide further information about any changes to the data relevant to a particular extraction and will also provide any appropriate metadata at the time of application.

Foundation Phase covers pupils from the age of 5-7. Key Stage 2 covers pupils from 7-11 years of age.  Key Stage 3 covers pupils from 11-14 years of age.  Key Stage 4 covers pupils from 14-16 years of age.


Researchers seeking to access the PLASC or Pupil Attainment data should apply to the School Statistics team on or 029 2082 5060 providing details of the research and the information required.

The decision to release data will be made on a case-by-case basis and all data releases will be subject to a data access agreement.  Currently data are provided to researchers free of charge.  There is no standard time scale for receiving data, although it can be expected that most data extractions will be dealt with within 10-15 working days.  More complicated and time consuming enquiries may take longer.  Ultimately the decision to release the data rests with the Chief Statistician of the School Statistics team.

Data quality

The computerised systems used by schools to record and make returns include robust validation checks.  Further checks on the accuracy of data are made by the Schools Statistics team before the data are published or made available to researchers. 

The data are expected to be of a high quality.  However, there may be instances where pupil data are missing, for example, if a child did not attend school on the day of a GCSE exam assessment or when a child has previously been educated outside of the state system or moved to Wales from abroad.


In 2002, the Welsh Government decided to stop the tests at Foundation Phase.  Instead, optional teacher assessment materials were provided to schools in 2003 for use in English, Mathematics, and Welsh.

At the end of 2003, the Daugherty Report was commissioned by the Welsh Government to undertake a review of the country’s assessment procedures. Following the outcome of the Daugherty Assessment Review Group in 2004, Key Stage 2 tasks/tests were made optional in 2005 and Key Stage 3 tasks/tests were made optional in 2006.

At Key Stage 3, the National Curriculum consists of the “core subjects” of English and Welsh, Mathematics and Science, and the “non-core subjects” of Welsh second language, modern foreign languages, design and technology, information technology, history, geography, art, music, physical education and religious education. At Key Stage 4, only five National Curriculum subjects are mandatory (English, Welsh or Welsh second language, Mathematics, Science, and Physical Education) and schools have greater flexibility to provide optional subjects that meet the needs and interests of their pupils.

Independent schools and Pupil Referral Units (PRUs) do not produce a PLASC return.

Pupils who leave or join the education system in Wales between the PLASC census day and the time of the assessments (May to July) are not included in the dataset. Such pupils will either be missing pupil characteristics or an attainment level.

Care should be taken when comparing the performance of ethnic groups with relatively few pupils because results for such small groups will show more volatility year on year than for groups with larger numbers of pupils.

In the PLASC data collection, pupils and their parents are encouraged to choose the most appropriate ethnic background. However in 2010, the ethnic background for between around 12 and 16 per cent of pupils in the relevant key stages each year was chosen by the school after parents/pupils did not choose a category (and did not explicitly state that they did not want one recorded by the school). The category chosen by the school will have been made available to parents/pupils for amendment but in cases where it was not amended the chosen category may not reflect the ethnic background to which the pupils feel they belong.

Pupils from an ethnic minority background are not evenly dispersed around Wales. They are concentrated in four local authorities, and in particular schools within these local authorities. The educational policies in place in such areas may have an impact on the academic achievement of such pupils.

The PLASC and Pupil Attainment datasets are highly sensitive.  Researchers applying for the data will have to make a strong business case in order to be granted access, particularly where potentially disclosive data such as home postcode is requested.  Researchers will be expected to comply with the Data Protection Act.  Information about the Data Protection Act and further advice on how to use sensitive data safely and securely can be found under our section on Important Guidance on the ADLS website.


Each individual pupil record in PLASC can be linked to the corresponding Pupil Attainment data via the Unique Pupil Number (UPN).  Data can also be linked longitudinally using the UPN to trace pupils over time.

In theory it is also possible to compare PLASC and Pupil Attainment records with those from the English NPD.  Attainment comparisons with the Scottish and Northern Ireland education systems should be treated with caution due to differing examination systems.

Research users / comments

Please contact us with any comments regarding this dataset.

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