"Standard & Poor's lowered its credit rating on SLM Corp. (SLM) to just one step above junk territory and warned it could be cut further, saying the student lender better known as Sallie Mae faces pressure on funding, profits and credit quality," The Wall Street Journal reports. "The two-notch downgrade after the market closed Monday - to BBB- from BBB+ - was the latest blow for a company that in the past year has seen a $25 billion buyout deal fall apart, margins in its core federally guaranteed student loan business squeezed by cuts to government subsidies and difficulties raising funds in the wake of the credit crisis sparked last summer. Sallie Mae agreed to costly terms last month to secure commitments for a $31 billion credit line needed to fund its business over the next year. S&P raised doubt about that deal Monday, saying it is keeping Sallie Mae's ratings on watch for a downgrade given the possibility those commitments are subject to conditions that could keep the deal from closing as expected."