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About cookies

To help improve this site we place small files, known as cookies, onto your computer. Some are essential for the site to work properly, others are to improve the experience you have.

You can stop this site using non-essential cookies by updating your settings above.

Please note, if you have used the site in the past these cookies may still be on your computer - but by disabling them in your settings we will no longer access them.

You can also decide to stop this or any site from using any cookies. To learn more about cookies and how to manage them visit

How we use cookies

We use cookies for several purposes on this website – we’ve listed each of them below with more details about why we use them and how long they’ll last.

Cookies to improve your experience

You can tell us to stop using these at any time by updating your settings above.

Measuring website usage (Matomo)

We use Matomo to collect information about how people use our site, and rough demographics as to what groups of people are using our site. We do this to make sure it’s meeting your needs and to understand how we could improve it.

Matomo stores information about:

  • the pages you visit
  • how long you spend on each page
  • how you got to the site
  • what you click on while you're here

The following cookies are set by Matomo:

Cookies set by Matomo
_pk_cvarA short-lived cookie that temporarily stores data for your visit30 mins
_pk_sesA short-lived cookie that temporarily stores data for your visit30 mins
matomo_sessidThis is created when the opt-out feature is used and helps provide fraud preventionWhen you close your browser
_pk_refThis is used to store the attribution information the referrer initially used to visit the website6 months
_pk_idThis stores a few details about you as a user, such as the unique visitor ID13 months
_pk_testcookieThis checks whether your browser supports cookies, and is then directly deletedCreated, then directly deleted

Understanding our users' needs

We use Hotjar to better understand our users’ needs and optimise the experience of this website. It helps us understand users’ experiences (eg how much time they spend on which pages, which links they choose to click, what users do and don’t like, etc), which enables us to build and maintain our service with user feedback.

Hotjar uses cookies and other technologies to collect data on our users’ behaviour and their devices. This includes:

  • A device's IP address (processed during your session and stored in a de-identified form)
  • Device screen size
  • Device type (unique device identifiers)
  • Browser information
  • Geographic location (country only)
  • Preferred language used to display our website

Hotjar stores this information on our behalf in a pseudonymised user profile and is contractually forbidden to sell any data collected on our behalf.

The following cookies are set by Hotjar:

Cookies set by Hotjar
_hjDonePolls This is used to maire sure the same survey does not reappear if you've already filled it in.1 year
_hjMinimizedPollsThis is used when you minimise a survey widget - it makes sure that this stays minimised as you navigate through the website.1 year
_hjid Set when a user first lands on a page with the Hotjar script. It's used to persist the Hotjar User ID, unique to that site on the browser. This ensures that behavior in subsequent visits to the same site will be attributed to the same user ID.1 year
_hjTLDTestWhen the Hotjar script executes, it tries to determine the most generic cookie path to use, instead of the page hostname. This is done so that cookies can be shared across subdomains (where applicable). To determine this, Hotjar tries to store the _hjTLDTest cookie for different URL substring alternatives until it fails. After this check, the cookie is removed.when you close your browser
_hjCachedUserAttributesThis stores User Attributes which are sent through the Hotjar Identify API, whenever the user is not in the sample. Collected attributes will only be saved to Hotjar servers if the user interacts with a Hotjar Feedback tool, but the cookie will be used regardless of whether a Feedback tool is present.when you close your browser
_hjLocalStorageTestThis is used to check if the Hotjar Tracking Script can use local storage. If it can, a value of 1 is set in this cookie and is deleted almost immediately after it is created.under 100m/s
_hjIncludedInPageviewSampleThis is set to let Hotjar know whether that user is included in the data sampling defined by your site's pageview limit.30 minutes
_hjViewportIdThis stores information about the user viewport such as size and dimensions.when you close your browser

Essential cookies

Website operation

The system that runs our website sets cookies to allow it to run smoothly.

Essential cookies that allow the website to run smoothly
cookiesPrivacyUsed to remember your privacy preferences90 days
AWSALBUsed to make sure the website can cope with unexpected traffic2 years
AWSALBCORSUsed to make sure the website can cope with unexpected traffic2 years

NB: Cookie guidance wording adapted from cookies on, shared under the Open Government Licence.