To enable this service to function, we sometimes place small data files on your computer. These are known as cookies.

To learn more about cookies and how to manage them, visit Or please read on to find out more about how and where we use cookies.

How we use cookies

This service uses essential cookies in some places – we've listed each of them explicitly in a table below with more details about why we use them and how long they will last.

These essential cookies are used for site navigation and session management, and this service may not function correctly without them.

This service may use non-essential cookies in some places. These non-essential cookies are not required to make the service function correctly. If any non-essential cookies are used in this service, you will find them listed below.

Cookies that measure how you use the website

We use Google Analytics to measure how you and other visitors use this website. We do not allow Google to use or share any of that data.

Google Analytics sets cookies that store anonymised information that includes:

  • how you got to the site
  • the pages you visit on the site
  • how long you spend on each page
  • what you click while you are visiting the site.

Google Analytics cookies:

  • _gali
  • _gat
  • _ga
  • _gcl_au
  • _gid

How to manage cookies

You can stop cookies being downloaded by changing the settings on your browser. If you do this, you may not be able to use every feature on this website.

Find out how to manage cookies on popular browsers: