To help us understand how this site is used, and so improve it, we deploy Google Analytics.

For Google Analytics to function, first party cookies track visitor interactions with the site. There are strict limits to the amount and kind of information that these cookies record or report. Read more about privacy and Google Analytics.

Your use of this website signifies your consent to our using Google Analytics. Should you wish to opt out, Google has developed a browser add-on to let you do so.

There are many sites offering further information about cookies, tracking and privacy — for example,