For a percentage column, you enter the two columns you want to use for the percentage ratio.
Whatever column you use in the top box is considered the numerator, and the column in the bottom box is the denominator. You usually use a column that is part of a total in the top box, the totals column in the bottom box.
This is a simplified case to find out what percentage of your net income was generated in the third quarter. To do this, enter the third quarter column as the numerator, and the totals column as the denominator. Let's say the third quarter netted $450,000 of $1,000,000 income.
Sage 50 prints 45% in the column you set aside for percentage.