What it means: FFNMA is the stock symbol for Fannie Mae, a corporation created by Congress to support the secondary mortgage market. It buys mortgages from lenders, securitizes them, and sells the securities to investors. The index measures mortgage commitments (Mtg Com) for delivery (del) within 30 to 60 days; that is the required net yield on mortgage loans that lenders sell to FNMA, which in turn sells mortgage-backed securities to investors.
How it's used: It's an index that is used primarily by lenders that sell their loans to Fannie Mae. The lenders use it to price their loans. It has little direct impact on ordinary investors.