You want to sum them up and calculate the percentage of each number upon that sum. To get the result as percentage you would multiply it by 100. So 4 contributes 40 and 6 contributes 60 to their sum 10.
Positive percentage change is an increase and negative is a decrease.
DV V1 100 V2 - V1 V1 100 percentage change. Just as you can calculate the percentage increase between two positive numbers you can do the same for negative numbers. C3-B3 The difference we calculated can have positive value or negative value meaning the change in value can be positive and negative. The difference is simply calculated by subtracting the column C values from column B values.