Excel® 2010 Bible

Chapter 12. Working with Dates and Times

IN THIS CHAPTER

An overview of using dates and times in Excel

Excel date-related functions

Excel time-related functions

Many worksheets contain dates and times in cells. For example, you might track information by date, or create a schedule based on time. Beginners often find that working with dates and times in Excel can be frustrating. To work with dates and times, you need a good understanding of how Excel handles time-based information. This chapter provides the information you need to create powerful formulas that manipulate dates and times.

NOTE

The dates in this chapter correspond to the U.S. English language date format: month/day/year. For example, the date 3/1/1952 refers to March 1, 1952, not January 3, 1952. I realize that this setup may seem illogical, but that's the way Americans have been trained. I trust that the non-American readers of this book can make the adjustment.

12.1. How Excel Handles Dates and Times

This section presents a quick overview of how Excel deals with dates and times. It includes coverage of the Excel program's date and time serial number system, and it offers tips for entering and formatting dates and times.

12.1.1. Understanding date serial numbers

To Excel, a date is simply a number. More precisely, a date is a serial number that represents the number of days since the fictitious date of January 0, 1900. A serial number of 1 corresponds to January 1, 1900; a serial number of 2 corresponds to January ...