You create spread curves to derive allocation factors that Oracle Projects uses to automatically distribute quantity, cost, and revenue amounts across a range of PA or GL periods.
You can assign a spread curve to resource classes and planning resources. The spread curve that you select for a resource class is the default spread curve for all planning resources that you define for the resource class. You can override the default spread curve assigned to a planning resource at any time. For more information on defining resource classes, see: Resource Classes.
You create a spread curve by specifying a series of weighting values for a range of ten spread points. You can create your own spread curves, use one of the following predefined spread curves as-is, or modify one of the predefined spread curves.
Even. Spread curve with a linear distribution that uses the following spread curve point values: 10-10-10-10-10-10-10-10-10-10.
Back Loaded. Spread curve with a back-loaded distribution that uses the following spread curve point values: 0-5-10-15-20-25-30-35-40-45.
Front Loaded. Spread curve with a front-loaded distribution that uses the following spread curve point values: 45-40-35-30-25-20-15-10-5-0.
Fixed Date. Spread curve with a fixed date distribution. You specify the fixed date when you assign the spread curve. No spread curve point values are associated with this spread curve.
S Curve. Spread curve with an S-shaped distribution that uses the following spread curve point values: 18-10-8-10-15-17-18-17-15-8.
Bell Curve. Spread curve with a bell-shaped distribution that uses the following spread curve point values: 0-4-10-12-14-12-10-4-0-0.
Note: When you enter spread curve point values, Oracle Projects assigns a zero value to any spread point for which you do not specify an amount.
To derive allocation factors for time periods, Oracle Projects calculates a weighted average allocation factor for each time period by distributing the spread curve point values proportionately across the range of time periods beginning with the first spread curve point and the earliest time period.
For example, if the number of time periods over which amounts are to be spread is four, Oracle Projects allocates the combined value of 2.5 spread curve points to each period. This amount is calculated by dividing the maximum number of spread curve points by the number of periods (10/4).
Frequently, the transaction start date associated with a resource or task is after the start date of a time period, or the transaction end date occurs before the end date of a time period. When either of these situations occur, Oracle Projects takes into account the actual number of resource or task transaction days to determine how to allocate the spread curve point values over the full and partial time periods.
For example, if during the course of four monthly planning periods, a resource transaction covers only 15 days of a 30 day month for either the first or last month, Oracle Projects counts that month as .5 periods for purposes of determining the distribution of spread curve points across the time periods. In this case, Oracle Projects allocates the combined value of 2.8571 spread points to each full month planning period. This amount is calculated by dividing the maximum number of spread curve points by the number of periods corresponding to the transaction (10/3.5). Oracle Projects allocates 1.4287 spread points to the partial (half) month. This amount is calculated by dividing the maximum number of spread curve points by the number of periods corresponding to the transaction and multiplying this value by .5 [(10/3.5) * .5].
To calculate the weighted average allocation factor for each time period, Oracle Projects divides the total number of points in the spread curve range, or ten, by the number of time periods that make up the time period range over which amounts are to be allocated.
For example, if you use the predefined Back Loaded spread curve to allocate amounts over four periods, Oracle Projects would determine the following allocation factors for each period:
Period 1: 10.0, which is the sum of Points 1 and 2, plus one half of Point 3, or [0 + 5 + (.5 * 10)]
Period 2: 40.0, which is the sum of one half of Point 3, plus Points 4 and 5 [(.5 * 10) + 15 + 20]
Period 3: 72.5, which is the sum of Points 6 and 7, plus one half of Point 8, or [25+30 + (.5 * 35)]
Period 4: 102.5, which is the sum of one half of Point 8, plus Points 9 and 10, or [(.5 * 35) + 40 + 45]
To determine the allocation percentage associated with the allocation factor for each period, divide each allocation factor by the sum of the allocation factors for all periods. Using the allocation factors derived in the preceding calculations, Oracle Projects would calculate the following allocation percentages to distribute amounts to the four periods:
Period 1: 4.44%, (10/225)
Period 2: 17.78%, (40/225)
Period 3: 32.22%, (72.5/225)
Period 4: 45.56%, (102.5/225)
When deriving the allocation factors and percentages associated with the ETC amounts for forecasts, Oracle Projects uses only the spread point values corresponding to the ETC time period. Therefore, the sum of allocation factor amounts used to calculate the allocation percentages for ETC amounts is the total of the allocation factors in the ETC time period, not the total of the allocation factors for all periods.
To create a spread curve, perform the following steps:
Navigate to the Create Spread Curve page.
Enter a name and, optionally, a description.
Enter an effective from date and, optionally, an effective to date.
Optionally, choose a different calculation precision value to change the default rounding precision for reporting the calculated spread amounts.
Optionally, choose a different display factor to change the default value for displaying the calculated spread amounts.
Optionally, specify the name of a spread curve that you want to use from a software solution other than Oracle Projects.
Note: This option is available only if you set up Oracle Projects to use spread curves from another software solution.
Specify a factor for each spread point.
Note: Oracle Projects assigns a zero value to any spread point for which you do not specify an amount.