Saudi Arabia's money supply grew 13.6 percent on year in January, compared with 13.3 percent in December, while the central bank's foreign assets surged 21.9 percent compared with January 2011, data from the Saudi Arabian Monetary Agency (SAMA) has showed. M3, the broadest measure of money supply and an indicator of future inflation, was SR1.235 trillion ($329.2 billion) in January, up from 1.087tn riyals in the year earlier, higher than the SR1.224 trillion in December, according to the data posted on SAMA's website. SAMA's net foreign assets rose to SR2.035 trillion in January, from SR2.007 trillion in December, and SR1.668 trillion in January 2011. Saudi Arabia, which has filled its coffers with surplus income from oil exports over the last decade, has drawn on its reserves to fund record budgets and keep its $400 billion five-year infrastructure development program on track. Last year, it earmarked additional funds to implement new housing projects. While this spending helped the Arab world's largest economy grow, banks have remained relatively hesitant to extend credit. Lending to the private sector rose to SR872.7 billion in January, from SR858.4 billion in the month earlier, and up from SR781.6 billion in January 2011. Bank claims on the private sector tripled between the boom years of 2003 to 2008.