Someone might tell you that Plymouth, New Hampshire only has a handful of violent crimes per year. They might also tell you that NYC has thousands more violent crimes per year. That makes Plymouth sounds so much safer, but in order to know for sure, we have to set the numbers into context, asking how many crimes per capita (or per person) each location has. Small pieces of information (such as how many children in a certain school go without breakfast each morning) are more illuminating if they are presented in relationship to other pieces of information (such as the poverty level of the town, the subsidized meal programs at the school, the start time of the school day, the funding formula for the school district, etc.).