We know because we talk to players and read there quotes in the press. They've told us, we know.
Another point
If 'directors' paid Faddy's wage last year, he was a bonus player. We saved nothing on the wage bill when he left so we can't count him as a replaceable. We can't say we lost 4, we get 4 in, unless of course, the 4 we bring in get paid the same amount as 3 who left.