Each week on the Excel Diet your goal is to lose one pound. Since there are seven days in a week each day you need to lose 1/7 of a pound which is 0.1428 lbs.
Once you reach your goal you'll try to maintain your weight below that goal.
The daily goal and your weight are used to determine how to eat and exercise for the day. If you're ahead of your goal you can increase your food and decrease your exercise. If you're behind your goal you need to eat less and exercise more.
The Excel Diet just requires you to enter your starting weight and it will calculate the daily goal for you.