Annual Reports

The BIPM Annual Report on Time Activities compiles the information on the data and computational process for Coordinated Universal Time (UTC) over one year.

BIPM Annual Report on Time Activities

Time Signals


Time Dissemination Services


BIH Annual Report (extract)


  • Since 2009 only electronic versions of the Annual Report have been published (on the internet), giving easy access to individual sections and tables.

  • Until 1987 the Bureau International de l'Heure (BIH) was responsible for the maintenance of UTC, and published all relevant information in the BIH Annual Report.