Duration calculation fields are used to calculate values from data entered into Duration fields in an event form.
Functions similar to those used in simple Calculation fields can be entered into the Calculation settings. The Format of the resulting value can be specified in the advanced field properties.
In the example above, Total time is a Duration calculation field and it uses a formula to display the sum of two Duration fields (Race 1 and Race 2). Since the data is entered into the Duration fields using the mm:ss.S format, we've set the Format of the Duration calculation field to the same option.
For Duration fields that are part of a table, you should use the Table duration calculation instead.