Option

Description

Contribution Percentage

Defines the percentage of the total to which this field contributes.

Count

Counts the number of records based on a selected field and rolls it up to the highest level.

Count Distinct

This calculation provides you with an easier way to determine the number of unique observations in a sample. For example, you can define a count distinct calculation on the investment type field to determine in how many separate investment types a portfolio is invested.

The count distinct calculation operates like the same command in SQL query tools. The calculation retrieves the number of unique observations in a sample. For example, a count distinct value of 1, 5 and 8 is 3. A count distinct value of 1, 3, 3, 5 and 8 is 4.

Group Percentage Fields

The Group Percentage rollup is closely related to the percentage field. The difference is, when more than one grouping level is used, instead of relating the percentage of a security to the highest level of the report, the securities are broken down to a percentage of 100 in their own grouping level. Null is displayed for all securities within a group when that group level value is (0.00).

Harmonic Mean Fields

To obtain the harmonic mean, first take the reciprocal of each number, next take the usual average, then take the reciprocal again (because reciprocal is the same as un-reciprocal; therefore, the operation is its own inverse).

For example, to find the harmonic mean of 10 and 20, first take 1/10 and 1/20, find their average, which is 3/40, and then take the reciprocal of that, 40/3.

In algebra, the harmonic mean H of two numbers A and B is:

1 / ( (1/A + 1/B) / 2)

or:

1/m = 1/2 (1/A + 1/B)

Maximum

The Maximum rollup field takes the highest value being populated in the selected field and rolls that value to the highest grouping level. For example, the rollup field is defined as maximum (Market Value). The highest market value is displayed at the highest grouping level

Mean Fields

The mean rollup field takes the average of all of the records in the selected fields and then rolls that value up to the highest level. The following example takes the mean of market value.

Median Fields

The Median rollup field is an alternative to the mean calculation. The median is the middle number when records are arranged in ascending or descending order. For example, the median of 1, 5, and 8 is 5. When there is an even number of records, the median is calculated as the mean of the two middle numbers when the records are arranged in ascending or descending order. For example, the median of 1, 5, 8 and 14 is (5+8)/2 = 6.5.

Minimum Fields

The Minimum field takes the lowest value in the selected field and rolls it up to the highest level.

Percentage Fields

The Percentage Rollup field calculates the percentage of each security based on a selected field and rolls it up to the specified level. In the example below, the percentage is based on the market value field.

Ratio Fields

Two fields are required. The following example uses Base Value and Second Value. The report ratio is determined by the following function:

Report Ratio (Base Value, Second Value) = Second Value / Sum (Second Value) * Base Value

The Sum (Second Value) is the sum of the second value for the entire report.

Report Ratio Fields

This calculation is based on three fields:

Ratio (Base Value, Second Value, Third Value)

For example, the three fields used Market Value, Cost, and Shares. Their values are:

MV = $450,000

Cost = $400,000

Shares = 1,000

The calculation being performed is:

Base Value / Second Value * Third Value.

In the example it would be Market Value / Cost * Shares, or:

450,000 / 400,000 * 1,000 = 1,125

So the resulting ratio value would be 1,125.

Standard Deviation Fields

The standard deviation is a statistic that tells how tightly all the various examples are clustered around the mean in a set of data. When the examples are tightly bunched together and the bell-shaped curve is steep, the standard deviation is small. When the examples are spread apart and the bell curve is relatively flat, there is a relatively large standard deviation.

The standard deviation for population in this example is 14.14.

The calculation is as follows:

Calculate the mean value of 50, 40, 30, 20, and 10. That is:

(50+40+30+20+10) / 5 = 30

Population i.e. number of values used in the calculation of standard deviation = 5.

Standard Deviation for population is:

Square Root ( (50-30)2 + (40-30)2 + (30-30)2 + (20-30)2 + (10-30)2 / 5) = 14.14

Standard Deviation for Population

Similar to Standard deviation except that instead of working with a complete set of numbers, you only have a sample. N-1 is used for a more conservative estimate especially with smaller samples. As the size of the sample increases, N-1 has less effect on the results.

Sum Fields

The Sum rollup field adds the values of each security from the field that the rollup was based on and rolls the value to the specified level.

Weighted Average Fields

Weighted Average is a calculation using a field based on another field. For example, you may want to see what the weighted average of a price compared to the quantity held of that security and roll it up to the portfolio level.