CRM 2015 introduces calculated fields. You create calculated fields in the same way as regular fields but select Calculated for the field type instead of Simple.
Calculated fields are only available for the following data types:
- Single Line of Text (all formats)
- Option Set
- Two Options
- Whole Number (also has Rollup capability)
- Decimal Number (also has Rollup capability)
- (not Floating Point Number)
- Currency (also has Rollup capability)
- Date and Time (also has Rollup capability)
Depending on the data type a calculated field can be set to the value of other fields, expressions that involve other fields and functions that operate on fields on the entity or related parent entities. Optional conditional tests provide support for branching and varying values depending on the value of a field in the entity or parent entity.
NOTE: if a calculated field exposes a value from a secured field then field security does not apply to the calculated field.