Yes, looking around at ratings articles for GMB I've seen them comparing figures of 700-800k with Piers to 300k when they launched, even though they launched with figures of 700-800k.
I know with breakfast TV they used to do a reach rating too as back in the 90s they'd put them in the Radio Times and I think they ranged from around 5m for The Big Breakfast through to 12m or so for GMTV, but then you'd see other figures saying they got a tenth of that figure which must have been the average. It does make comparing breakfast TV and radio shows somewhat tricky now TV seems to stick to the average and radio just goes on reach.
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