If you can select data on your graph, you can most probably modify it as well. If you move the mouse while data is selected, the data point will be modified on the graph and in the data grid.
The graph and statistics will interactively update themselves to accommodate the new data. In this example, you should be able to see that the regression line has bee recalculated.
Different graph types allow different ranges of movement. For example, in horizontal box and whisker plots you will only be able to move the data point in the horizontal axis.
