Legend.Position (PowerPoint)
Returns or sets the position of the legend on the chart. Possible return values are xlLegendPositionBottom - Below the chart, xlLegendPositionCorner - In the upper-right corner of the chart border, xlLegendPositionCustom - A custom position, xlLegendPositionLeft - Left of the chart, xlLegendPositionRight - Right of the chart, xlLegendPositionTop - Above the chart.
ActivePresentation.Slides(1).Shapes(1).Chart.Legend.Position = xlLegendPositionBottom