Step 1 The scatter plot that suggests modelling the data with an exponential function Have following properties. The data points on the graph should not be scattered far away from each other. The shape of the curve should either exponentially increasing upwards or exponentially decreasing downwards. Mostly the data points should be above the x - axis. Step 2 The one in which there is a declining trend in the data the graph of such datasets are called Exponentially decaying. While the other in which there is increasing trend is called exponentially increasing.