New Delhi, Sept. 20 -- Investors often assume that an actively managed mutual fund will differ significantly from its benchmark, as the fund manager has the flexibility to change allocations and take active bets in an attempt to generate higher returns.

But portfolio data for mid-cap funds shows that the difference can be quite significant across schemes, with a few funds having more than half of their portfolio overlapping with the Nifty Midcap 150 TRI.

Portfolio overlap refers to the percentage of a fund's holdings that are also present in its benchmark index. According to a Value Research post on X, "mid-cap fund overlap with the Nifty Midcap 150 TRI ranges from 11.6% to 51.9%".

This matters because the benchmark itself consists of ...