About chart subtypes
In addition to the main chart types, you can choose a number of subtypes. The area, bar, cone, line, pyramid, and tube are main chart types that have a stacked subtype and a percent stacked subtype. After selecting one of the main chart types, you can choose its stacked subtype to position positive or negative values above or below the origin of the chart. Alternatively, you can choose a percent stacked subtype to show the contribution of individual items to the whole.