Apple Numbers '08 - Manual (Page 219)

Chapter 12 Dictionary of Functions 219
COUNTA
The COUNTA function counts the number of arguments and referenced cells that are
not empty.
COUNTA(value, [value, . . .])
 value: A reference to one or more cells or an argument containing a value.
Notes
To count only cells or arguments that contain numbers or dates, use the COUNT
function.
Examples
Given the following table:
COUNTA(A1:E1) returns 5.
COUNTA(A2:E2) returns 5.
COUNTA(A3:E3) returns 5.
COUNTA(A4:E4) returns 5.
COUNTA(A5:E5) returns 2.
COUNTA(1, "a", TRUE, FALSE) returns 4.
COUNTA(1, SUM(4, 5)) returns 2.