ONS currently has a contract with a commercial provider for the provision of digitising statistics from the 1921, 1931, 1951 and 1961 Census published county and topic reports to improve accessibility and thereby make better use of the data.

This procurement intends to fulfil requirements with a single supplier that will enable the authority to provide access to all users of population statistics and enable further analysis to aid understanding of social change at national and a range of lower level geographies.

The proposal is for the expected delivery of digitized data for two censuses per year for two years - Year 1 1921 and 1931, Year 2 1951 and 1961 ONS is seeking to establish a contract with an organisation that can provide a service to digitize the statistics and convert to structured data that can be exported and subsequently hosted on the Nomis system.

Because of time constraints (two censuses per year) and the volume of data extraction that involves, the requirements are that the procured service must include, at a minimum: • An already existing automated system or tool for extraction of the data from the images taken from the census volumes which is capable of performing the following:- o Identification of errors created in the original publications. o Error correction and quality assurance to validate extracted data prior to delivery. o Creation of a system to assign missing values. o The ability to handle both 'fixed' (standard rows and columns) and 'complex' (variable row counts and multi-dimensional combinations) tables and supplementary information pages such as classifications and commentary. o Production of a data model to extract information from complex historical census geography hierarchy that varies between censuses to allow for time-series analysis o Supply structured data in .csv format to facilitate potential use with an API.

Additionally, data extraction, presentation and delivery methods must be well-defined and of high quality with an enhanced level of quality assurance to meet our statistical requirement.

How to register Please email clare.jones@ons.gov.uk with an outline of your services.

Please use the reference CS-25-060 on the email.

We will be scheduling follow-up one-to-one sessions to discuss your responses to the above questions once the notice has expired.