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Fair Stock Trades

Alejandra Collopy wears safety glasses as she works the lab. She is surrounded by various pieces of equipment and many hanging wires.
Credit: R. Jacobson/NIST

With modern high-speed trading, stock market activity generally exceeds one billion dollars per minute. Financial service firms need precise time stamps at every step of a transaction to ensure robust and fair financial markets and to allow for accurate audits. 

U.S. stock markets are required to synchronize to NIST time. They receive real-time, remote calibration of precision clocks and oscillators through NIST’s Time Measurement and Analysis Service (TMAS). The calibration is traceable to NIST standards for time and frequency, at an accuracy better than a microsecond (one-millionth of a second). 

In addition to the stock market, this service benefits many other sectors of the economy, including manufacturing, aerospace, aviation, calibration laboratories and communication. Owners and operations that critically depend on knowledge of time rely on the precision and accuracy of NIST’s TMAS.

Learn more about TMAS

Created March 17, 2025, Updated March 20, 2025