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This service puts small files (known as ‘cookies’) on to your computer.

These cookies are used to:

Find out more about how to manage cookies

Google Analytics cookies

We use Google Analytics to collect information about how you use the service. This information helps us to improve the service.

The Google analytics cookie collects and stores information about:

Name Purpose Expires
_ga Used to identify unique users and inform referring sites, visitor and session counts 2 years
gat Used to manage the rate at which page view requests are made 10 minutes
__utma Like _ga, this lets us know if you’ve visited before, so we can count how many of our visitors are new to a certain page 2 years
__utmb This works with _utmc to calculate the average length of time you spend on the site 30 minutes
__utmc This works with _utmb to calculate when you close your browser when you close your browser
__utmz This tells us how you reached our site (e.g. from another website or a search engine) 6 months

Google isn't allowed to use or share our analytics data with anyone.

Introductory message cookie

When you first use the service, you may see a cookie message appear at the top of the screen. Once you’ve seen the message, we store a cookie on your computer so it knows not to show it again.

Name Purpose Expires
seen_cookie_message Stores a message to let us know that you have seen our expanatory cookie message 30 days