A newborn baby's weight is recorded each month, from the day of birth until 12 months. One baby's weights, in pounds, are recorded below:

7.20, 9.15, 11.01, 12.56, 14.04, 15.43, 16.52, 17.68, 18.77, 19.69, 20.22, 21.05, 21.90


What is the average amount of monthly weight gain, rounded to the nearest hundredth of a pound, each month?
A) 1.13
B) 15.79
C) 1.23
D) 16.52