A = Age, P = Period, C = Cohort. All isolines are spaced at 5 years. Suicide rates are stratified by firearm involvement. Suicide rates for each birth cohort can be visualized along its specific diagonal C isoline, with corresponding ages and periods along A and P isolines, respectively. For instance, diagonal isoline C:1964 represents the suicide rate specific to the cohort of men born in 1964. The hexagon where C:1964 intersects with vertical isoline P:2010 and diagonal isoline A:46 represents their suicide rate in year 2010, when they were 46 years of age. Likewise, suicide rates for each period can be visualized along its specific column or vertical P isoline; and suicide rates for each age group along its specific diagonal A isoline.