The figures came from the Celtic Annual Reports. There is a five year summary at the back of each with net profit/loss figures so all it takes is a few reports (they are available online) and a calculator (not a Seville one).
I didn't look too closely at Celtic's debt because I have never considered debt to be particularly relevant. In my view, profit and loss are far more important. However, just to put your assertion into perspective, Celtic announced in February of 2011 that they had a £9M bank debt. In addition to this you have to add Trade debt to the calculation so the actual figure will be quite a lot higher.
Hope this helps.