"It would be shown at the end of the day."
The exchange had circulated the decision to brokers two weeks ago. Bandaranaike says the decision was taken in consultation with members, and such practices are followed elsewhere including Singapore and Malaysia.
Sri Lanka's investors have a habit of chasing stocks that foreign investors trade which can increase volatility both ways.
"The CSE has noted that displaying real time information on foreign purchases and sales on the ATS has resulted in market manipulation and/or discriminatory practices amongst market participants," the exchange said a statement to member brokers on February 15. From today foreign purchases and sales numbers would be displayed as zero until end of trading.