Stacked curves display the total of different variables in an informative way.
The accompanying graph shows how the total number of Methodists in Bradford grew, the slumped, then grew again in the 19th century. There were a lot of difficult Yorkshire men in Bradford in the 1850’s (there still are) and they had an almighty row, the police were called.
To prepare data for a stacked curve graph, enter data for each of the variables. In the graph alone there are the total figures for Bradford east, west and south.
BridPlot will then compute the sums of the variables for each x value, and display them.