Access to mortgages is really a very small part of the 'equation'.
This is a 'general' list of certain economic assumptions from a year or so ago:
http://i716.photobucket.com/albums/ww165/Back_at_the_Ranch/GOP%20Idiots/Econ-Ass_2Q09.jpg
This has nothing to do with the Fed --- it was contained within budget documents. My point is that when determining prospective rates the Fed makes certain economic assumptions and reviews substantial data when setting rates.
Since Nixon (Arthur Burns, Fed Chairman) and 'stag-flation' the Fed's 'objective' has been to control inflation. Rates are essentially set in order to prevent the economy from 'overheating' and driving inflation. (Volcker as Fed chair is a matter which I won't cover here.)
But then 'It' happened. In the Summer of 2007 financial markets 'froze'. A little more background:
Financial institutions 'settle' accounts between themselves. In 2007 they decided they didn't want to play at central bank rates. They would 'play' but demanded settlements 150-200 basis points above central bank rates.
To put it simply, they didn't trust each other and didn't want to trade in the financial paper normally used to settle accounts. They effectively became 'illiquid'.
In order to prevent rates from jumping 1-2% overnight in August of 2007, central banks began pumping cash into the system with 'reverse repos'. In subsequent months the Federal Reserve developed a handful of special options and collateral programs for banks to keep them 'liquid' --- so much so that since 2007 they have pumped around $2 trillion into the system (this does not include TARP from the Treasury).
I told you all that because, remember the objective: ""manage the financial system to keep inflation at bay""
It is estimated that the Federal Reserve will have to 'unwind' at least $1 trillion from the system while managing rates to promote economic growth and control inflation while keeping financial institutions 'solvent'.
I hope I didn't confuse you - LOL
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