Overview: Time Intervals

Analyzing or categorizing data by time intervals can be difficult due to the various types of financial calendars that exist. Each organization has its own policy of when the financial year starts and ends, as well as how the year is broken down into financial periods.

To make it easier for Monarch Classic users to analyze and categorize data by time intervals, Monarch Classic 10.5 introduces the Time Intervals feature. With this feature, you can define your organization’s financial year and periods (or that of the data being analyzed), then use that information when summarizing data, as well as in the 14 new date functions. In addition, the formatting masks for each of the 13 time intervals can be user-defined. These settings are saved in the model and can also be saved to the registry to be set as defaults when creating a new model.

In order to utilize the Time Intervals, they must first be defined for the company or data being analyzed. This is performed via the Time Intervals Options dialog. After the Time Intervals are defined, they can be used in the new date functions that leverage Time Intervals. In addition, they can also be used in the Matching Tab of Summary Key Values.

The following table lists each time interval and a corresponding description. These can be accessed in the Time Interval drop-down list on the Matching tab of the Key Field dialog.

Interval	Meaning
Calendar Year	One full calendar year from Jan 1 through Dec 31.
Calendar Half-year	One-half of a calendar year. The six calendar months from Jan 1 through Jun 30 or from Jul 1 through Dec 31.
Calendar Quarter	One-fourth of a calendar year. Three calendar months starting Jan 1, or Apr 1, or Jul 1, or Oct 1.
Calendar Month	One calendar month.
Calendar Week	One calendar week. See the Calendar Intervals discussion below.
Day	A single day. Starts at midnight (00:00:00) and goes to the following midnight.
ISO8601 Year	An ISO8601 year, i.e., the 52-53 ISO8601 weeks associated with a particular calendar year.
ISO8601 Week	An ISO8601 week. See the ISO8601 Intervals discussion below.
Fiscal Year	One full fiscal year. There are two types: month-based and week-based. See the Fiscal Intervals discussion below.
Fiscal Half-year	One-half of a fiscal year, defined as two fiscal quarters.
Fiscal Quarter	One-fourth of a fiscal year. See the Fiscal Intervals discussion below.
Fiscal Period	One fiscal period. Either one month or one 4- or 5-week period. See the Fiscal Intervals discussion below.
Fiscal Week	One fiscal week. See “Fiscal Intervals” discussion below.

Calendar intervals

The calendar intervals are, by and large, self-explanatory with the exception of “Calendar Week”. Calendar weeks are typically 7-day periods starting on a designated day of the week. By definition, a calendar week interval may not cross a calendar year boundary. Consequently there is always a partial week interval at the start and/or the end of the calendar year, to account for the fact that 7 does not divide evenly into 365 (or 366) days.

Using the Time Intervals Options dialog, you can specify exactly how the year is broken into calendar week intervals. There are three supported methods of doing so:

Week 1 starts on January 1st, regardless of what day of the week that may be. Weeks are then numbered from 1 to 53, where week 53 is a partial week consisting of the 1 or 2 days left over at the end of December. This week numbering is identical to the Monarch Classic Week function when the 2nd parameter is omitted.
Full weeks start on a specified day of the week, which may be any of the 7 possibilities. The first full week of the year starts on the first occurrence of the designated day on or after January 1st. If January 1st happens to be the designated day, then weeks are numbered 1 to 53 exactly as in method #1. If, as more commonly happens, the first occurrence of the designated day is after January 1st, then the days in January prior to that first full week are counted as week 0. Thus, weeks are numbered from 0 to 52 (or 53 in some years). This week numbering is identical to the Monarch Classic Week function where the 2nd parameter specifies the designated start day for full weeks.
Same as method #2, but the partial first week, if any, is counted as week 1. Thus weeks are numbered from 1 to 53 (or 54 in some years). This week numbering is identical to Excel’s “WeekNum” function, except that in Excel, weeks may only be designated as starting on Sunday or Monday, whereas Monarch Classic allows weeks to start on any designated day of the week.

ISO8601 intervals

ISO8601 is an international standard for dealing with date and time values. In this standard a week is defined as 7 days starting on a Monday, and a year consists of either 52 or 53 full weeks, starting on the Monday closest to January 1st. Thus it frequently happens that the first week of an ISO8601 year actually includes days (up to 3) from the end of the previous calendar year. Likewise the last week of an ISO8601 year may include up to 3 days from the start of the next calendar year.

Fiscal intervals

In an attempt to satisfy a wide range of possible definitions for fiscal intervals, Monarch Classic supports two distinct types of fiscal years: month-based and week-based.

Month-based

Month-based fiscal years consist of 12 calendar months, starting on the first day of a designated starting month. For instance, one might specify a starting month of October, in which case the fiscal year would run from October 1st to the following September 30th. A month-based fiscal year thus always contains 365 or 366 days.

Month-based fiscal years are subdivided into half-years, quarters, and months (called, more generally, “periods”) in the obvious way. They may also be divided into fiscal weeks, with the understanding that there is always a partial week at the start and/or end of the fiscal year, since it is asserted that no fiscal week may contain days which fall outside the fiscal year.

Using the Time Intervals Options dialog, it is possible to specify exactly how a month-based fiscal year is broken into fiscal week intervals. The options are completely parallel to those described above for calendar weeks; the only difference is that the week numbering is started with respect to the first day of the fiscal year (e.g., October 1st) instead of with respect to January 1st.

Week-based

Week-based fiscal years consist of 52 or 53 fiscal weeks, where each week is a full 7 days starting on a designated day of the week. The complete specification for this type of fiscal year consists of three pieces of information: a week starting day, a reference date, and a start/end method. The week starting day is the day of the week (e.g., Monday) on which each week starts. The reference date is a given month and day which forms a specific point with respect to which the fiscal year begins or ends. The start/end method specifies precisely how the start or end of the fiscal year is related to the reference date.

For example, a fiscal year might be defined as “starting on the first Monday on or after May 15th”. In this case the week starting day is “Monday”, the reference date is “May 15th”, and the start/end method is “starts on or after”. In the year 2008, for instance, May 15th was a Thursday, so in that case the fiscal year would run from 2008-05-19 (the first Monday on or after May 15th) up to and including 2009-05-17 (the day before the start of the next fiscal year). Fiscal years are typically named for the calendar year in which they end, thus the fiscal year running from 2008-05-19 through 2009-05-17 would be called ‘fiscal year 2009’.

Clearly, the exact starting and ending dates of a week-based fiscal year may shift a bit from year to year depending on where the week starting day happens to fall with respect to the reference date. Even so, a week-based fiscal year always contains 364 or 371 days, that is, 52 or 53 full weeks.

The week starting day may be any of the 7 possible days. The reference date may be any valid month/day combination (except for February 29th, for obvious reasons). The start/end method has four supported possibilities:

The year starts on the first week starting day on or after the reference date.
The year starts on the week starting day closest to the reference date.
The year ends on the last week ending day on or before the reference date.
The year ends on the week ending day closest to the reference date.

The week ending day is inferred from the week starting day.

There are no standardised methods how week-based fiscal years should be divided into half-years, quarters, and periods. Monarch Classic supports two basic methods of doing these divisions:

The year is divided into four 13-week quarters.
The year is divided into thirteen 4-week periods.

When division method #1 is chosen, each quarter may be further subdivided into 4- or 5-week periods using any of three patterns: 4-4-5, 4-5-4, or 5-4-4. When division method #2 is chosen, the periods are obviously each 4-weeks long, but it is still possible to use “Fiscal Quarter” intervals, in which case a quarter is arbitrarily defined as 13 weeks and the quarter boundaries do not, in general, align with the period boundaries.

Regardless of the method chosen for dividing the year into quarters and periods, half-years are always defined as two quarters.

One further subtlety of week-based fiscal years is how to account for the extra week (i.e., week 53) in those years which happen to have 53 weeks. When using division method #1 the user specifies the particular quarter (1-4) and period within that quarter (1-3) into which the extra week should be placed. When using division method #2 the user specifies the period (1-13) into which the extra week should be placed.

See Working with Time Intervals for related information.