The U.S. Financial Industry Regulatory Authority (FINRA) is enhancing over-the-counter (OTC) equity market transparency expanding the available data to the entire market, the U.S. regulator announced on Monday.

FINRA is expanding on the data that it already makes available on the trading that takes place in dark pools and on other sorts of alternative trading systems (ATSs).

The non-ATS OTC volume is being published on a delayed basis, starting today. Following the same schedule that it uses for ATS volume, data on certain securities is delayed two weeks, while other data is delayed by four weeks. The additional data represents approximately 20% of all U.S. equity trading volume, FINRA says.

“Enhanced disclosure of over-the-counter trading serves the interests of investors and other market participants by enabling them to better understand a firm’s trading volume and market share,” says Richard Ketchum, chairman and CEO of FINRA, in as statement.

“Taken together with FINRA’s current reporting on alternative trading systems, the new data completes a holistic picture of trading that investors can use to make better-informed trading decisions.