Your old system of rating exchange traded funds (ETFs) just isn’t cutting it anymore.

The ETF market is booming, and it’s leading research firms to take another look at how they analyze these funds.

Standard & Poor’s is planning to launch new ETF rankings in the coming months, and Morningstar overhauled its ETF research center earlier this year. When it comes to the way they look at these funds, both firms are putting more emphasis on their analysts’ outlook on the individual holdings of each fund, reports Eleanor Laise for the Wall Street Journal.

When it launches its research arm, S&P will cover about 550 of the nearly 700 ETFs available. It will offer recommendations as well as show how a fund allocates its assets and will give commentary on a fund’s market niche.

Morningstar did something similar, whereas before, its only rating system was the star rating. It was a backward-looking measure of a fund’s risk-adjusted past performance. Its new valuation rating is more forward-looking.