With the true calorie balance now known, adjust your calorie target to match your body's burn rate. Suppose you started assuming your body burned 2200 calories a day and planning to eat 1700 calories a day in order to lose a pound a week. After the first month of the diet, you examine the trend chart and discover you actually lost weight faster than you planned: at the rate of 1 1/4 pounds a week, evidence of a daily shortfall of 600 calories instead of the 500 you intended.
As long as you're carefully following the meal plan you know your calorie intake is close to 1700. The only possible cause of the discrepancy, then, is that you're actually burning 2300 calories a day rather than the 2200 you guessed. Now you get to choose; if you feel fine losing 1 1/4 pounds a week and prefer to get the diet over with so much the quicker, stay with your original meal plan. If, on the other hand, the extra calorie shortfall is bothering you, simply adjust your meal plan to supply 1800 calories a day: the 2300 you really burn minus 500 for the planned weight loss. In a couple more weeks, you should see a trend line that's falling one pound a week.