As a former teacher( thirty-seven years), I can tell you that a school system is only as good as what an individual child gets out of it. As far as the "stats," Livingston ranks very well. Those stats will be validated for your child if and when he/she reacts favorably to the environment, teaching styles, and curricula offered. There is no guarantee that a child will either be as successful or more successful than any other student in the school, or that he/she will have as pleasant an experience. My caution would be , yes, consider the numbers provided and the commentary on individual experiences, but also consider these factors: does your child function better in small or large groups, does he/she respond favorably to highly competitive situations or ones of a more collegial nature . No one knows your child as well as you do, and education is more than how well everyone else does.
There are many communities like Livingston in the Essex County area that offer award winning school systems. I would be happy to discuss them with you.