There are five different types of fact:
A calculation that produces a numeric or date result based on a fact. There are five simple fact types all accessed by clicking "SUM" and selecting from the drop-down.
SUM adds all of the values within each dimensional grouping. It uses the basic arithmetic operators +, -, *, and /, to build an expression as well as parenthesis, (), to enforce precedence.
MIN returns the smallest value in the Fact results and allows string concatenation.
MAX returns the largest value in the Fact results and allows string concatenation.
AVG returns the arithmetic mean (average) of the values in the Fact results.
COUNT returns the number of source elements in the Fact (1 per row from the Source Query, counted when grouped by the Smart Column's levels).
Incorporates simple Facts within a larger expression and gives the result, e.g. multiply the result of a SUM by the result of a COUNT. Each simple Fact component should be built within the Embedded Fact itself.
Compares the result of a Simple fact expression against a Threshold, and returns the corresponding Pick state.
Free Form Threshold
Similar to the Threshold Fact type but allows you to define your own thresholds using a pick list.
Aggregated Pick State
Return the min or max Pick List state for a given Pick List. Can be used to show the extreme cases to be found within a group of elements. Min and max values are determined by the order of pick items within the Pick List i.e. top Pick List value is min and bottom value is max.
For a more detailed explanation on Facts and the Fact Builder see Aggregation - Facts.