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How are the Number of Weekdays and Weekend Days in each Month Determined in MOVES?

See More Frequent Questions about MOVES and Related Models.

For any given month, MOVES assumes that 5 out of every 7 days in the month are ‘weekdays’ and 2 out of every 7 of days in the month are ‘weekend days.’ For example, MOVES assumes that January has (5/7)*31 weekdays and (2/7)*31 weekend days. The current version of MOVES does not incorporate leap years, so February is assumed to have 28 days (and thus, 20 weekdays and 8 weekend days) every year. The default number of days for each month are included in the ‘monthofanyyear’ database table and are constant across years.

To calculate an emissions inventory that reflects the actual number of days in a month in a particular year, do the following:

  1. Using MOVES, calculate an emissions inventory for a weekday and a weekend day in the month.
  2. Multiply the weekday inventory by the number weekdays in the month and the weekend day inventory by the number of weekend days.
  3. Sum the two values.

MOVES and Related Models

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Contact Us About MOVES and Related Models
Contact Us About MOVES and Related Models to ask a question, provide feedback, or report a problem.
Last updated on June 20, 2025
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