Hi @em1535,   As far as I see, your DATA step creating dataset ANALYSIS.COUNT works perfectly on survival data with a discrete time scale like year 1, 2, 3, 4, 5 with corresponding variables TSMK_1, ..., TSMK_5 describing the smoking status in each of those time periods. However, you apply this program to data with time measured on a continuous scale with values ranging at least from 0.1314 to 85.8809.   So, the failed attempt of retrieving the smoking status at time 48 from the five-element array TSMK_ raises the question: What are the five time intervals on your continuous scale that the variables TSMK_1, ..., TSMK_5 correspond to? ... View more