SLR is Statutory Liquidity Ratio. It’s the percentage of Demand and Time Maturities that banks need to have in any or combination of the following forms:
ii) Gold valued at a price not exceeding the current market price,
iii) Unencumbered approved securities (G Secs or Gilts come under this) valued at a price as specified by the RBI from time to time.
The maximum limit of SLR is 40% and minimum limit of SLR is 24%. It’s 24% now. This restriction is imposed by RBI on banks to make funds available to customers on demand as soon as possible. Gold and G Secs (or Gilts) are included along with cash because they are highly liquid and safe assets.
The RBI can increase the SLR to contain inflation, suck liquidity in the market, to tighten the measure to safeguard the customers’ money. In a growing economy banks would like to invest in stock market, not in G Secs or Gold as the latter would yield less returns. One more reason is long term G Secs (or any bond) are sensitive to interest rate changes. But in an emerging economy interest rate change is a common activity.
You can find the latest rates from the RBI website itself. Here I am giving the link. Mouse over on reserve ratios (on Right hand side) to see SLR and CRR.