So the rate of change is the same as the gradient, or the slope.
To work out this you need to do the change in y/ the change in x.
So we take 2 points you are given in the table- e.g (1,5) and (2,1)
So the change in y is from 5 to 1 so it is -4 and the change in x is from 1 to 2 so is 1.
Then you have -4/1 which is just -4.
Let me know if you have any questions!
