watch out 10y Trea

--mortgage investors use 10 trea as a hedge --sales of mortgages dropped 20%, less demand for 10 trea --influence of mortage over treasuries increased as mortage mkt quardupled to 10.9 tril since 2001 --more than 6 tril of securities backed by morgage loans are outstanding, comparing to 4.5 tril treasuries market --100 bil of treasuries trade every day, hedging surged to as much as 45% of that amount when yields drop a quarter percentage point.