That might be true if the Figures actually counted 'every' TV. They just have random samples so no figures are exact but they disregard 'switched off tvs'. So if half the TVs they count are switched on, and half of them are watching the rugby, they'll say that half the country is watching rugby (as opposed to the actual quarter that was).
(and personally speaking its easier for me to get out for a point on a Wednsday night than it is a Saturday/sunday afternoon, but thats another story)
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