THE BRONX - The number of New York City students in kindergarten ? eighth grade considered obese is thinning out, according to a new survey from the Centers for Disease Control and Prevention.

At a press conference today, Mayor Michael Bloomberg and School Chancellor Dennis Walcott noted that these numbers represent the biggest decline in childhood obesity by any large city in the country.

The study noted that in the 2010-11 school year, 20.7 percent of public school students in K-8 were obese overall, although this varied by borough.

The Bronx had the highest obesity rate at 23.3 percent and Manhattan had the lowest rate, with 19 percent.

The sharpest decline was seen among children 5-6 years old, who went from a 20.2-percent obesity rate to an 18.2-percent obesity rate.

While the results are good, many people say more has to be done to fix the obesity problem because one in five children in grades K-8 are still obese.