First thing, ensure that your data step code RUNS properly Thank you, I am new to SAS and have not tried to create an example dataset before and didn't realize the ;s would cause errors. Really wonder if X07 is 2007 and X10 is 2010 why there are no X08, X09, etc. Seems like a very FUNKY data structure. Yes, one of the many challenges with this data is that the X measurements are *not* evenly spaced. At different points, they have occurred at 1, 2, 3, or 4 year intervals. It is, as you say, very funky.   State the RULE for selecting the value. If you say "X14" that does not tell use what the response might be when the choice is between X12 and X16 or any other such pair for some reason. I would prefer to default to the earlier measurement when two measurements are equidistant from the event. I don't know to articulate this as a rule. Since you say have 30 X values is there some point at which a single value might be "too far" from the year for actual use? If so what is that difference and what to do? For now, nothing is too far. In an ideal world, I would be able to create a second variable that indicated how far the X measurement was from the event, but I have been focused on just trying to figure out how to make my main variable.    Thank you, again.  ... View more