How do you create formula-based UDF's?

1) Click the Projects
menu and select Enterprise Project Data, or click the Administer
menu and select Enterprise Data.
2) In the Enterprise Data pane, expand Projects and click Project UDFs.
3) On the Project UDFs page:
a. Click
Add (Insert).
b. In the User Defined Field, double-click and type a name.
c. In the Data Type field, double-click and choose a type from the list.
d. In the UDF Type field, double-click and choose Manual or Formula from the list.
Notes:
-Choosing Formula enables the fields in the Formula detail window, allowing you to define a formula or statement to calculate the value of the field. If no calculation is required, choose Manual.
-You cannot filter views by UDFs calculated on the basis of a formula.
4) In the Formula detail window, define a formula or statement.
5) In the Indicators detail window, define a graphical indicator.
6) On the Project UDFs page, click
Save (Ctrl+S).