“Unlike other mutual funds, equity ETFs are passive funds and hence we can ensure minimal tracking error involved into it,” he added.The retail and HNI portion of the AUM rose 50 per cent from `1,102 crore in March 2014 to `1,656 crore in March 2015 on the NSE platform, according to the data from the largest bourse. The AUM of equity ETFs on the BSE could not be ascertained immediately. Some of the fund houses with equity ETF offerings include Reliance, SBI, Axis, Kotak, IIFl and Goldman Sachs.