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This site places small files, known as 'cookies', onto your computer to collect information about how you browse.

These cookies aren't used to identify you personally.

You’ll normally see a message on the site before we store a cookie on your computer.

Find out more about how to manage cookies.

Measuring site usage

We use Google Analytics and Google Optimize software to collect information about how you use this site. We do this to help make sure the site is meeting your needs and to help us make improvements.

We store information about:

  • the pages you visit and how long you spend on each page
  • how you got to this site
  • what you click on while you're visiting this site
  • which variation of a page you've visited when we are testing out small design changes using Google Optimize

Any information on site usage is received in a way that we can't identify individuals. For example, we never receive your name or address.

We don't make any attempt to find out the identities of people visiting this site and we don't allow Google to do this either.

All information we get through cookies and analytics will be treated in confidence. We’ll never sell, trade or give your details to third parties, unless we're required to do it by law.

Find out more about security and privacy in Google Analytics.

Opt out

You can opt out of Google analytics cookies.

Details of cookies used by this site

This table shows all cookies used by this site, and what each is used for.

Name Purpose Expires
ASP.NET_SessionId Stores a temporary unique identifier for your session When you close your browser
ARRAffinity Keeps track of which of the website servers users are connected to, if we have to scale out the website when it is under a high load the affinity cookie ensure the users connection isn’t lost. When you close your browser
_ga Used to count how many people visit this site by tracking if you’ve visited before 2 years
_gid Used to count how many people visit this site by tracking if you’ve visited before 24 hours
_gat Used to throttle request rate 1 minute