1029.8.19.12. If a taxation year of a taxpayer or a fiscal period of a partnership has fewer than 51 weeks, the amount determined under section 1029.8.19.9 in respect of the taxpayer for the year or of the partnership for the fiscal period, as the case may be, is to be replaced by the proportion of that amount that the number of days in the year or the fiscal period, as the case may be, is of 365.