Excel's Formula - sisman

Chapter 6: Working with Dates and Times 147
Similarly, the serial number equivalent of 1 second is approximately 0.00001157, obtained by the
following formula (1 divided by 24 hours times 60 minutes times 60 seconds). In this case, the
denominator represents the number of seconds in a day (86,400).
=1/(24*60*60)
In Excel, the smallest unit of time is one one-thousandth of a second. The time serial number
shown here represents 23:59:59.999, or one one-thousandth of a second before midnight:
0.99999999
Table 6-2 shows various times of day, along with each associated time serial number.
Table 6-2: Times of Day and Their Corresponding Serial Numbers
Time of Day Time Serial Number
12:00:00 AM (midnight) 0.0000
1:30:00 AM 0.0625
3:00:00 AM 0.1250
4:30:00 AM 0.1875
6:00:00 AM 0.2500
7:30:00 AM 0.3125
9:00:00 AM 0.3750
10:30:00 AM 0.4375
12:00:00 PM (noon) 0.5000
1:30:00 PM 0.5625
3:00:00 PM 0.6250
4:30:00 PM 0.6875
6:00:00 PM 0.7500
7:30:00 PM 0.8125
9:00:00 PM 0.8750
10:30:00 PM 0.9375
Entering times
Like with entering dates, you normally don’t have to worry about the actual time serial numbers.
Just enter the time into a cell using a recognized format. Table 6-3 shows some examples of time
formats that Excel recognizes.