It's very difficult to measure print. Some advertisers would measure it at their cash out, asking where we found out about their sale.
You have to be very careful with the click-through rates as well. Nearly half the traffic on the Internet is robots crawling around and doing the clicking for you. There has been quite a lot in the news recently about problems Facebook and Google are having with that.
The digital platforms allow all kinds of analytical reporting that we simply can't provide in the same way with print. John Hinds went quite extensively through Totem Research that had been done, and that's how we measure.