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Chronograph watches can measure and display elapsed time. Usually three subcounters on the dial display the elapsed seconds, minutes and hours.

The perpetual calendar complication displays the day, date and month, but it requires less adjustment than an annual calendar. This complication knows the number of days in each month but it also knows the year so that it will automatically adjust for leap year. The next time a perpetual calendar will have to be adjusted is in the year 2100.