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Sample Formulas to Calculate Traditional Calendar Week Numbers

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This document contains a URL to a patch which demonstrates how to calculate full weeks when only three or four days are in a week, and offers possible workarounds.

Download Description

In 1-2-3, the @DATEINFO function used with the attribute 4 returns the week of the year as an integer from 1 to 53. Week number one is always assigned to the week containing January first; however, under traditional calendars, the first week of the year is the first week containing more than three days in January. To calculate the week number based on traditional calendars, you should create a formula based on nested @functions, or you should create an @function using LotusScript. The 123_ALMANAC.ZIP file demonstrates this issue and contains several possible workarounds.


@DATEINFO Returns Unexpected Result When First Week of January is Less Than Four Days Document #: 168370

Installation instructions

1. Click the URL,, and download the file to your machine. 2. Unzip the file and extract it into the default working folder for 1-2-3, usually c:\LOTUS\WORK\123.

Download package

DOWNLOAD RELEASE DATE LANGUAGE SIZE(Bytes) Download Options 11/30/1998 US English 36100 FTP

Document information

More support for: Lotus End of Support Products
Lotus 1-2-3 for Windows

Software version: 9.0, 9.1, 9.5, 9.6, 9.7, 9.8

Operating system(s): Windows

Reference #: 4004008

Modified date: 30 October 2003

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