Extend
Purpose 
Allows a value in non-repeatingField to be used with every repetition in a repeating field.
Format 
Extend(non-repeatingField)
Parameters 
non-repeatingField - any non-repeating field (a field defined to contain only one value), or an expression that returns a reference to one
Data type returned 
text, number, date, time, timestamp, container
Originated in 
FileMaker Pro 6.0 or earlier
Description 
Use the Extend function with calculations involving both repeating and non-repeating fields. Without the Extend function, the value in non-repeatingField is used only with the first repetition in the repeating field.
Examples 
Extend(TaxRate) * Quantity * ItemPrice returns 1.197, .6606, and 1.497 when TaxRate contains .06; the repeating field Quantity contains 1, 3, and 5; and the repeating field ItemPrice contains 19.95, 3.67, and 4.99.
Item Count * Extend(if(Company Size > 100; Reduced Price; Price)) returns $1250, $500, and $750 when Reduced Price contains $50; the repeating field Item Count contains 25, 10, and 15; and Company Size is greater than 100. If Company Size is less than 100 and Price contains $100, this calculation returns $2500, $1000, and $1500.
Related topics 
Functions reference (category list)
Functions reference (alphabetical list)
About formulas
About functions
Defining calculation fields
Using operators in formulas