Naming Basics Best practice recommendations are to create a chart placing independent variables on the horizontal, x-axis and dependent variables on the vertical, y-axis.

How Excel Charts Work A chart has an x-axis range and a y-axis range to show the correlation between two different data sets. The x-axis is the horizontal category line.

If you have uneven distribution of data in your Excel chart, here is a better way to change the automatic axis settings.

In this graph the intervals on the bottom axis are unequal, making it difficult to read. Scales should either start at zero, or be concertinaed (squashed) as shown in the y-axis in the above graph.