This is the first rounding rules area of the Price Rounding table (PRO). The system looks at this area first to determine if the cent value should be rounded to the value in the fields "If over dollar by up to" and "Then reduce below dollar to."
For example: One of the lines of your table is set up as follows:
If you have an item with a cost of $2.04 and a desired gross margin of 50%, the system calculates a retail price of $4.08 without price rounding. Using the table, the system determines that the cents value of .08 is less than .09, so it rounds the pennies down to .99. The retail price with price rounding is $3.99.
If the cent value does not match the "If over dollar by up to" field, the system goes to the next area of rounding rules, Rule 2.