A report released by the School Nutrition Association (SNA) surveyed the progress of implementing the Child Nutrition and WIC Reauthorization Act of 2004, which required all school districts participating in the National School Lunch Program to adopt a so-called wellness policy by the start of the 2006-2007 school year. With health infrastructure feeling the increasing burden of health problems associated with bad diets, the motivation to instil good eating habits into children while they are still young is high. While the rate of obesity in children has not yet reached the epidemic proportions in children that it has in adults, statistics show it is on the rise. Data taken at different intervals as part of the National Center for Health Statistics' National Health and Nutrition Examination Survey (NHANES) demonstrates an increase between the 1976-1980 survey period and the 2003-2004 survey period. The prevalence of overweight children aged two to five years increased from five percent to 13.9 percent. The prevalence for children aged six to 11 went from 6.5 percent to 18.8 percent, while for the 12 to 19 age group, the rate grew from five percent to 17.4 percent. The food industry has in part been blamed for this gap in nutrition due to the successful marketing of unhealthy products geared at younger age groups. Less and less physical activity is another oft-cited factor. However, this shift in lunchroom policy has made room for food companies to either undo any bad work, or to gain access to schools with their healthy or functional products. Mars Snackfood US, which boasts three best-selling snacks sold in the vending category, said it anticipated these challenges and developed a line of nutritious snacks for school vending. Its Generation Max snacks are fortified with vitamins and minerals, including calcium, vitamins D and B, and are trans-fat free. In its report, SNA compiled data from a survey of 976 school nutrition directors conducted in May 2007. They indicated a strong level of control over in-house changes, but felt less empowered regarding what kids eat outside of school meal programs. These more external sources include those available to kids through school stores and fundraisers, as well as food rewards given by teachers and food served at classroom party celebrations. Another challenge highlighted by those responsible for nutrition in schools was the ability for school programs to find affordable products that meet policy nutrition standards, acceptance by students and compliance with policy.