A woman counts yuan banknotes as she sells tickets for a job fair in Beijing in this file photo. China’s official foreign exchange trading platform operator adjusted the yuan midpoint mechanism yesterday, sources said, the latest move to help curb speculation on the exchange rate. China Foreign Exchange Trade System shortened the reference period of yuan trading against its trade-weighted basket to 15 hours, between 4:30 p.m. from the previous trading day to 7:30 a.m., compared with the previous 24 hours, banking sources said. SD-Agencies