age smoking.status alive interviewed ageQ 18-24 smoker 53 55 21 18-24 nonsmoker 61 62 21 25-34 smoker 121 124 29.5 25-34 nonsmoker 152 157 29.5 35-44 smoker 95 109 39.5 35-44 nonsmoker 114 121 39.5 45-54 smoker 103 130 49.5 45-54 nonsmoker 66 78 49.5 55-64 smoker 64 115 59.5 55-64 nonsmoker 81 121 59.5 65-74 smoker 7 36 69.5 65-74 nonsmoker 28 129 69.5 75+ smoker 0 13 79.5 75+ nonsmoker 0 64 79.5