Calculation of weekly income
Periodical payments are normally made either weekly (or in some multiple of weeks), or monthly (or in some multiple of months). The key question is – how many payments are made, or are due to be made, in the course of a whole year? The most common situations are: The appropriate conversion to a weekly amount is shown after the dash. The program does this automatically if other than 'Week' is picked in the associated combo box. Normal monetary rounding is applied where the intermediate result is not an exact multiple of a penny.

Where payments of income are made in periods of other than weeks or months, they are converted to a weekly amount by dividing by the number of days in the period and multiplying by 7. So, for example, a payment that is made every 20 days would be converted by the factor 7/20. Payments in this form are rare.

In practice most forms of income are paid weekly, four-weekly or monthly; some kinds of investment income are paid quarterly. Monthly payments are normally made on a fixed day of the month, while the payment day of four-weekly payments will vary over the course of the year.