Chief Statistician’s update: plans to improve the coherence of Welsh language statistics in Wales

Darllenwch y dudalen hon yn Gymraeg

December 2022 saw the first release of data about the Welsh language from Census 2021. This showed that the number of Welsh speakers had fallen to 538,300. This contrasted with some other sources which suggested figures had been rising.

There are several other data sources available that provide some information about the Welsh language that we can use to monitor trends in the period between censuses. This suite of data sources each have their own strengths and limitations when looking at Welsh language statistics.

Household surveys, such as the Annual Population Survey (APS) and the National Survey for Wales, typically provide higher estimates of the number of people able to speak Welsh than the census, and both the ONS (Differences in estimates of Welsh Language Skills) and the Welsh Government (Welsh language data from the Annual Population Survey: 2001 to 2018) have explored possible reasons for some of these differences in the past.

While household surveys typically provide us with higher estimates of Welsh-speaking ability, they have generally moved in a similar direction to the census estimates. However, with the 2021 census results, this is the first time that the census has estimated declining numbers of Welsh speakers and household surveys have estimated increasing numbers. A blog post published alongside the first census release explored the data in more detail, including what other data sources had been telling us about the Welsh language in the period between 2011 and 2021. This rest of this blog post provides an update to the December 2022 blog post and outlines how both the Welsh Government and the Office for National Statistics (ONS) will be collaborating to explore some of the differences seen between the census and other data sources.

The chart shows the results from the Annual Population Survey from 2001 to the end of March 2021. In 2001 there were 834,500 Welsh speakers. The trend decreases until 2007 and then increases again to 844,000 by the end of March 2021. The results of the 2001, 2011 and 2021 Census have also been plotted on the same chart to show that the Census estimates for the number of Welsh speakers are significantly lower; over 300,000 lower.

Improving our understanding of Welsh language statistics

Due to the range of data sources available, it is not simple for users of statistics on Welsh language ability to reconcile the different estimates, especially the fact that some estimates show increasing numbers of Welsh speakers, while others show decreasing numbers. This can make it challenging to know how to use these statistics to inform Welsh language public policy.

We have been working closely with our colleagues in the ONS over the past few months to explore further what we can do to better understand some of these differences. Today, we have published a collaborative work plan that aims to explore these issues in more detail.

A key part of this work is to link Census 2021 data to ONS survey data via the Integrated Data Service. This innovative data linking project, one of the first projects to use the IDS, will allow us to learn more about the groups of people who respond differently between the census and ONS surveys, about their Welsh language ability, and to look at their characteristics. This will be the starting point for helping to improve our understanding and coherence of Welsh language statistics across a range of data sources.

Findings from this project can then be used to explore differences between other sources, such as the Pupil-Level Annual School Census (in relation to the estimates of Welsh language ability of school children) and the National Survey for Wales (in relation to the estimates of Welsh language ability of adults).

The workplan also outlines how we will try to understand not only how these data sources are different, but why. This includes investigating why the differences between the data sources are changing over time by looking in more detail at aspects of survey methods and design.

And finally, alongside the work already underway at the ONS on transformation of the Labour Force Survey, ONS will consider how to further improve the range of statistics on the Welsh language by assessing options to collect information about people who are able to speak Welsh but live outside Wales. This is of growing importance, given that our population is becoming increasingly mobile.

A taskforce comprising of myself and other Welsh Government analysts together with ONS officials has been set up to oversee this work. We will provide regular updates through this blog and our statistics and research pages. This work will be key as we look towards the future of Welsh language statistics.

Stephanie Howarth
Chief Statistician