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Excel Object Model: Axes

A chart's axes object contains all axis objects that belong to that chart.
An individual axis is refered through the axes object with a couple of «coordinates» 
dim ax as axis
set ax = axes(tp, gr)
tp is one of the xlAxisType enumeration: xlCategory, xlSeriesAxis or xlValue
gr is one of the xlAxisGroup enumeration: xlPrimary, xlSecondary.

See also

The chart and the axis object.
Excel Object Model

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