<P> Statistics referencing the prevalence of bullying in schools may be inaccurate and tend to fluctuate . In a U.S. study of 5,621 students ages 12--18, 64% of the students had experienced bullying and did not report it . </P> <P> Proactive aggression is a behavior that expects a reward . With bullying each individual has a role to defend . Some children act proactively but will show aggression to defend themselves if provoked . These children will react aggressively but tend to never be the ones to attack first . </P> <P> There have been two subtypes created in bully classification; popular aggressive and unpopular aggressive . Popular aggressive bullies are social and do not encounter a great deal of social stigma from their aggression . Unpopular aggressive bullies, however, are most often rejected by other students and use aggression to seek attention . </P> <Ul> <Li> In a recent national survey 3,708,284 students reported being a perpetrator of bullying in the U.S. school system . </Li> <Li> Studies have shown bullies actually report more success in making friends than other children . </Li> <Li> Bullying behavior in perpatrators is shown to decrease with age . </Li> <Li> Developmental research suggests bullies are often morally disengaged and use egocentric reasoning strategies . </Li> <Li> Adolescents who experience violence or aggression in the home, or are influenced by negative peer relationships, are more likely to bully . This suggests that positive social relationships reduce the likelihood of bullying . </Li> <Li> The diagnosis of a mental health disorder is strongly associated with being a bully . This trend is most evident in adolescents diagnosed with depression, anxiety, or ADHD . </Li> <Li> Poor theory of mind is associated with bullying . </Li> <Li> 25% of students encourage bullying if not given proper education and information about the consequences of bullying . </Li> <Li> A study by Lisa Garby shows that 60% of bullies in middle school will have at least one criminal conviction by the age of 24 . </Li> </Ul>

What is the main cause of students not reporting bullying