[excel] excel plot against a date time x series

There is one way to do this, as long as you have regular time intervals between all your date-time values - make the x-axis consider the values as text.

in Excel 2007, click on the chart - Go to the layout menu (contextual menu on clicking on the chart) , choose the option Axes->Primary Horizontal Axes-> More Horizontal Axes Options
Under Axis Type, choose "Text Axis"

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