Plotting Times of Day

Richard has some source data that shows the date and time displayed in the format dd/mm/yy hh:mm, but when he creates a chart from that data, the only thing that is plotted is the date. He is wondering if there is a way of plotting the times on the chart, as well as the date.

There are several ways you can approach this issue, depending on the type of chart you want to create. If you create an X-Y scatter chart, the date and time should plot automatically. This is not the case if you choose to create a bar, column line, or any other type of chart. In those cases, the X axis is created from equally spaced values, so you won't get exactly what you want.

If you don't want to use a scatter chart, then you could simply modify the data in your source. Add a column that represents the hour of the day, derived through the HOUR function. For instance, if you have your date and time in column B, add a column C and fill it with formulas such as =HOUR(B3). The result is a bunch of numbers representing the hour of the day, 0 through 23. This can chart very easily in any manner desired.

If that doesn't fit your needs, then go ahead and create the chart as you normally would. Then, right-click the X axis and choose Format Axis from the Context menu. You should see the Format Axis dialog box. Make sure the Numbers tab is selected. (Click here to see a related figure.)

Choose one of the formats for the axis under either the Date or Time categories. You may have to play a bit with your selection, experimenting to find out what works best. Quite honestly, what works best in one situation won't necessarily work best in another because of the nature of the data being charted.

You can find more information about formatting time values on an axis at this Web site:

http://www.mrexcel.com/tip032.shtml