If your category axis displays numbers like 1, 2, 3, 4 instead of the values you want, you may have selected a line chart instead of an xy (scatter) chart when you created the chart. In the Chart Type dialog box (Chart Type command, Chart menu), click XY (scatter) in the Chart type box. If you want lines to connect the markers, click one of the xy (scatter) sub-types that has a line.
Make sure to enter the data for the xy (scatter) chart in the correct order on the datasheet. The top row (or left column) of your data selection represents the x series, and each successive row (or column) represents a y series. Both the x and y values should be entered and formatted as numbers, not text.
Make sure the correct row or column is plotted on the x axis.
My xy (scatter) chart doesn't use my values along the horizontal (x) axis.