This problem must be solved by using <em>Excel. </em>So, since we have two questions, let's solve this problem in two steps.
FIRST. Calculating the difference between the attendance totals for 2018 and 2017
Let's name x and y two variables, where:
x: the cell that contains the total of 2018
y: the cell that contains the total of 2017
So, we can storage this variables in cells in excel. So, we can storage x in, say, A1 and y in, say, A2. This is indicated in the Figure bellow. You just need to replace x and y for the correct values of the attendance totals
2. Copy the formula to the range g6:g11
By copying this formula to the range G6:G11, we will have that:
G6 = A2 - A3
G7 = A7 - A4
G8 = A4 - A5
G9 = A5 - A6
G10 = A6 - A7
G11 = A7 - A8