Microfinance is the provision of financial services including Credit, Savings, Insurance etc, to those sectors of economy, which are not serviced by traditional formal financial institutions i.e., commercial banks and non-banking financial institutions. Microfinance caters to the financial services needs of the poor and micro enterprises and is normally collateral-free short term facility whereas the commercial banks generally deal with corporate clients, SMEs and individuals with larger income levels and extend financing facilities primarily based on collaterals and borrowers capacity to repay.
Visit the below link regarding Statistics/Data on Microfinance
BANKSCOPE and DATASTREAM would probably be your best databases to look at. However, I think websites of relevant banks and respective banks' periodicals would also help you out in this regard.