4-4-5 calendar

The 4–4–5 calendar is a method of managing accounting periods. It is a common calendar structure for some industries such as retail, manufacturing and parking industry.

The 4–4–5 calendar divides a year into 4 quarters. Each quarter has 13 weeks, which are grouped into two 4-week "months" and one 5-week "month". The grouping of 13 weeks may also be set up as 5–4–4 weeks or 4–5–4 weeks, but the 4–4–5 seems to be the most common arrangement.

When a 4–4–5 calendar is in use, reports with month-by-month comparisons or trend over periods do not make sense because one month is 25% larger than the other two. However, you can still compare a period to the same period in the prior year, or use week by week data comparisons.

Its major advantages over a regular calendar are that the end date of the period is always the same day of the week, which is useful for shift or manufacturing planning, and that every period is the same length.

One disadvantage of the 4–4–5 calendar is that it has 364 days (7 days * 52 weeks), so that approximately every 5.6 years there will be a 53-week year, which can make year-on-year comparison difficult.

The 52–53-week fiscal year is a variation on the 4–4–5 calendar. It is used by companies that desire that their fiscal year always end on the same day of the week. Any day of the week may be used, and Saturday and Sunday are common because the business may more easily be closed for counting inventory and other end-of-year accounting activities. There are two methods in use:

Under this method the company's fiscal year is defined as the final Saturday (or other day selected) in the fiscal year end month. For example, if the fiscal year end month is August, the company's year end could fall on any date from August 25 to August 31. In particular, the last fiscal week is the one that includes August 25 and the first fiscal week of the following year is the one that includes September 1. In this scenario, fiscal years would end on the following days:

The end of the fiscal year moves one day earlier on the calendar each year (or two days when there is an intervening leap day) until it would otherwise reach the date seven days before the end of the month (August 24 in this case) or earlier. At that point it resets to the end of the month (August 31) or earlier and the fiscal year has 53 weeks instead of 52. In this example the fiscal years ending in 2013, 2019, and 2024 have 53 weeks.

Under this method the company's fiscal year is defined as the Saturday (or other day selected) that falls closest to the last day of the fiscal year end month. For example, if the fiscal year end month is August, the company's year end could fall on any date from August 28 to September 3. In particular, the last fiscal week is the one that includes August 28 and the first fiscal week of the following year is the one that includes September 4. In this scenario, fiscal years would end on the following days:

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