Index mutual funds — a category that aims to mimic returns of benchmarks, like Nifty or Sensex — have seen their assets surge 60% over the past one year as better returns than schemes that invest in a broader set of stocks have drawn smart investors to them. As per data compiled by ETIG database, Index funds (excluding Exchange Traded Funds or ETFs) saw their assets jump from ₹3,773 crore in April 2018 to ₹5,275 crore in April 2019.