Baby growth percentile

BabyCenter calculator

Sex = boy, Age = 1 Month, Length = 22.25 inches, Weight = 10.75 pounds, Head circumference = 39.0 centimeters
Based on the data you submitted, your child falls into the following percentiles:Length = 50th percentile,Weight = 50th percentile,Head Circumference = between 25th and 50th percentile

This estimate seems quite low to me. From the chart, I can see that baby is about 75th percentile for all three aspects. He is even bigger when he was born, but now becomes more normal. I hope it's not because he is not eating well??

http://www.mybirthcare.com/favorites/babygrowthchart.asp is a better chart.