Excel chart: How to reverse the X axis of time series data

1. Click the axis for the categories, values, or series whose plotting order you want to change.

2. On the Format menu, click Selected Axis, and then click the Scale tab.

   Note Selected Axis is only available on the Format menu when a data series is selected.

3. To reverse the plotting order, do one of the following:
   • For categories, select the Categories in reverse order check box.
   • For values, select the Values in reverse order check box.
   • For series in 3-D charts, select the Series in reverse order check box.

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If you have numerical data, don't make a "Line Chart", make an "XY Chart". This treats the X axis data as numerical values. If you look at more than the Line Chart and XY Chart icons, you will notice that you can apply styles that include markers and lines or lines only to both XY and Line charts.

Line charts are good for categorical X data (non-numerical labels) and for flexible axis scaling for actual dates (year-month-day) but not simple values like years.