RATE

In watchmaking, the term refers to the accuracy of a watch or movement, and the result of its measurement, with deviation expressed in seconds per day (s/d). In many chronometric test series, the term daily rate refers to this measurement taken over a 24-hour interval. The rate of watches is generally measured by acoustic detection (timegrapher), and more rarely by optical detection.

Useful links:

– Setting
– Chronometer certification (ISO 3159)