Calculating the Average Daily Requirements

Implementation Options

The system uses the calculation of the average daily requirements as the basis for calculating the dynamic safety stock.

Prerequisites

In Customizing for MRP, you have defined the parameters for calculating the average daily requirements in the range of coverage profile itself using the IMG activity Define range of coverage profile (Dynamic safety stock) . The individual parameters are:

  • Periods (month, week or PPC planning calendar period)

The periods are calendar periods, that is, the system calculates them from the calendar start of the period. A weekly period, for example, is calculated from Monday to Sunday and a month is calculated from the first calendar day to the last calendar day of the month.

  • Number of periods that are included in calculation of average daily requirements

  • Period length

  • Workdays

The system defines workdays using the factory calendar.

  • Calendar days

The system defines calendar days using the Gregorian calendar.

  • Standard days

You can specify, for example, that 20 days are to be used for the calculation of the monthly average.

Process Flow

  1. The system uses the defined parameters to determine the number of days used for calculating the average daily requirements. If the period is defined as a week , the period length as standard days (5 days) and the number of periods as 2, the system divides the total of the requirements by 10 days.

  2. The system then calculates the total of the requirements for this period.

Note Note

The system takes into account all requirements in the current period, even requirements that lie in the past but are still in the current period. For example, if the planning run is carried out in the middle of the month, then those requirements that were planned at the beginning of the month are also included in the calculation of the average daily requirements.

End of the note.

  1. The average daily requirement is calculated using the formula:

    Requirements in the specified number of periods / Number of days within the total period length

Caution Caution

With time-phased materials planning , the system does not calculate average daily requirements using the number of days defined in the profile. It calculates the average daily requirements using the number of days in the interval between the MRP date and the availability date to the next MRP date.

See also: Range of Coverage for Time-Phased Materials Planning

End of the caution.