I think that it's high time that some of the confusion about where we have earned money from sales, and whether those earnings have fallen, should be debunked. Using data from the transfermrkt website shows that, as Mike argues, the earnings from players early in Dario's reign came from players brought into the club. However, the majority of this came from players released by League clubs such as Lennon, Hignett, Platt et al. These totalled just over £3million up to 1996 (excluding sell on clauses), £2.7m of that coming from Lennon, Hignett and Ward. Since then we have brought in no players released by top clubs that have been sold on, a situation likely to pertain so long as young players at such clubs are paid salaries higher than our top players.
Dario was also adept, with Neil Baker's expertise, at discovering nuggets from non-league clubs. However, the majority of such players played very successfully for us but did not attract a fee when leaving (one thinks of Macca, Smithy, Little, Steve Jones and many others). There have been exceptions of course, notably Luke Varney and John Brayford, but the total profit on fees reveived from such talent is approximately £4.3m since 1990 and nothing since Brayford's sale in 2010.
The first sale of an Academy graduate was in 1990 (Rob Jones) and the second not until 5 years later (Rob Edwards). Since then sales have come more regularly but there has always been a year or two of no sales or smaller fees received. In total the club has received about £30million in fees (in 26 years), excluding sell-on clauses. It is perhaps more instructive to look at a 5 year average of income from the Academy to take account of the 'fallow' years, and this shows that since 1998 there has only been one period when this average is lower than £1million per annum - 2000 to 2004, when we spent most of our time in the second tier. Thanks largely to the sale of Powell (which looks increasing like a great bit of business by the club!) the average income from the Academy over the past 5 years is over £2million pa.
We haven't made a profit from any purchase since Brayford and none from a player bought from a League Club since Luke Rodgers was sold in 2007.
It is pretty clear that the financial sustainability of the club over the past 25 years has been down to the Academy, which has also brought the fans some of the most entertaining football in the lower leagues and a lot of pride in our former players. This is not to say that there should not be a review of the operations of the Academy, or indeed the rest of the club. This is standard practice in any business and the Alex should be no different - it may not be at the top of the Board's agenda right now but it should be pretty close.
I shall now sit back and wait for my analysis to be picked apart

- and don't take the precise numbers as gospel, but they should be pretty accurate!!