In any case in which the employee has not been employed for a sufficient period to enable a calculation to be made under the preceding provisions of this Chapter, the amount of a week's pay is the amount which fairly represents a week's pay.
In determining that amount the employment tribunal—
shall apply as nearly as may be such of the preceding provisions of this Chapter as it considers appropriate, and
may have regard to such of the considerations specified in subsection (3) as it thinks fit.
The considerations referred to in subsection (2)(b) are—
any remuneration received by the employee in respect of the employment in question,
the amount offered to the employee as remuneration in respect of the employment in question,
the remuneration received by other persons engaged in relevant comparable employment with the same employer, and
the remuneration received by other persons engaged in relevant comparable employment with other employers.
The Secretary of State may by regulations provide that in cases prescribed by the regulations the amount of a week's pay shall be calculated in such manner as may be so prescribed.