On the first page of the Chart Wizard you can choose a chart type.
An area chart shows values as points on the y-axis. The x-axis shows categories. The y-values of each data series are connected by a line. The area between each two lines is filled with a colour. The area chart's focus is to emphasise the changes from one category to the next.
Normal - this sub-type plots all values as absolute y-values. It first plots the area of the last column in the data range, then the next to last, and so on, and finally the first column of data is drawn. Thus, if the values in the first column are higher than other values, the last drawn area will hide the other areas.
Stacked - this sub-type plots values cumulatively stacked on each other. It ensures that all values are visible, and no data set is hidden by others. However, the y-values no longer represent absolute values, except for the last column which is drawn at the bottom of the stacked areas.
Percent - this sub-type plots values cumulatively stacked on each other and scaled as percentage of the category total.