I wish I were wrong. The 484m+1b were the revenues(net gain for investor --WaMu) for sales of MBS in 2006 and 2007.
So, the net gain was 0.75% (1.5b / 200b= 0.75%) after all the expenses, including the service charge.
It is logic. If WMI held 20-25% of equity of MBS. So, the net gain by the investors in MBS is 0.75% divided by 20% equals to 3.75%, which was closed to the mortgage rate after deducting all the expenses.
Therefore, WMI accumulated annual revenue of 37.5b.
300 b x 0.75% x 10 years = 22.5b
Plus
1.5b x 10 years = 15b
Total 37.5 b cash in for us