Page 271 - Excel 2007 Bible

18_044039 ch13.qxp 11/21/06 11:05 AM Page 228
Part II
Working with Formulas and Functions
If you enter a time only (without an associated date), into an unformatted cell, the maximum time that you
can enter into a cell is 9999:59:59 (just under 10,000 hours). Excel adds the appropriate number of days.
In this case, 9999:59:59 is interpreted as 3:59:59 PM on 02/19/1901. If you enter a time that exceeds
10,000 hours, the entry is interpreted as a text string rather than a time.
Formatting dates and times
You have a great deal of flexibility in formatting cells that contain dates and times. For example, you can
format the cell to display the date part only, the time part only, or both the date and time parts.
You format dates and times by selecting the cells and then using the Number tab of the Format Cells dialog
box, as shown in Figure 13.1. To display this dialog box, click the dialog box launcher icon in the Number
group of the Home tab. Or, you can click the Number Format control and select More Number Formats
from the list that appears.
The Date category shows built-in date formats, and the Time category shows built-in time formats. Some
formats include both date and time displays. Just select the desired format from the Type list and click OK.
FIGURE 13.1
Use the Number tab in the Format Cells dialog box to change the appearance of dates and times.

TIP When you create a formula that refers to a cell containing a date or a time, Excel automati-
TIP
cally formats the formula cell as a date or a time. Sometimes, this automation is very helpful;
other times, it’s completely inappropriate and downright annoying. To return the number formatting to the
default General format, choose Home ➪ Number ➪ Number Format, and select General from drop-down
list Or, use this shortcut-key combination: Ctrl+Shift+~.

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