4. Section 3 of the Principal Act is amended by inserting in subsection (1) the following definition:“ ‘defined fraction' means—
(a) in relation to service that occurred before the commencement of the Long Service Leave (Building and Construction Industry) (Amendment) Act (No. 2) 1996 —13/15; and
(b) in relation to service that occurred on or after that commencement—13/10;”.