I (SAS 9.3) have a dataset for a training course where students' block grades are in individual rows. If a student fails a block they are held back until the next class where they reattempt the block and must pass before they can continue in training.   I am wanting to create a "first-attempt only" dataset that contains only their block grades up until their point of failure. Conceptually I want SAS to look at each ID and within ID retain only the rows associated with the student's first training attempt. First training attempt is defined as their performance in the training class they started in (e.g., 202001).   For example, in the dataset below, student 1001 progressed through training in class 202001 until Block_3 where they failed. They then resumed training in class 202002 and finished all five blocks. For student 1001 I want to keep their performance in class 202001 (their first training attempt) and drop all observations of subsequent training classes (202002).   This is an example of my dataset. My goal is, within each ID, keep only the observations associated with the trainees first class. For 1001 that's class 202001, for 1002 that's class 202004, etc. ID Class Training_Block Grade Status 1001 202001 Block_1 88 PASS 1001 202001 Block_2 76 PASS 1001 202001 Block_3 68 FAIL 1001 202002 Block_3 71 PASS 1001 202002 Block_4 86 PASS 1001 202002 Block_5 90 PASS 1002 202004 Block_1 50 FAIL 1002 202006 Block_1 73 PASS 1002 202006 Block_2 91 PASS 1002 202006 Block_3 95 PASS 1002 202006 Block_4 71 PASS 1002 202006 Block_5 78 PASS 1003 202003 Block_1 76 PASS 1003 202003 Block_2 89 PASS 1003 202003 Block_3 80 PASS 1003 202003 Block_4 95 PASS 1003 202003 Block_5 97 PASS 1004 202008 Block_1 74 PASS 1004 202008 Block_2 70 PASS 1004 202008 Block_3 60 FAIL 1004 202009 Block_3 82 PASS 1004 202009 Block_4 68 FAIL 1004 202010 Block_4 72 PASS 1004 202010 Block_5 90 PASS   This is what I'm conceptually wanting SAS to do. Keep all observations with first class value within each ID and drop all subsequent class values within each ID: ID Class Training_Block Grade Status 1001 202001 Block_1 88 PASS 1001 202001 Block_2 76 PASS 1001 202001 Block_3 68 FAIL 1001 202002 Block_3 71 PASS 1001 202002 Block_4 86 PASS 1001 202002 Block_5 90 PASS 1002 202004 Block_1 50 FAIL 1002 202006 Block_1 73 PASS 1002 202006 Block_2 91 PASS 1002 202006 Block_3 95 PASS 1002 202006 Block_4 71 PASS 1002 202006 Block_5 78 PASS 1003 202003 Block_1 76 PASS 1003 202003 Block_2 89 PASS 1003 202003 Block_3 80 PASS 1003 202003 Block_4 95 PASS 1003 202003 Block_5 97 PASS 1004 202008 Block_1 74 PASS 1004 202008 Block_2 70 PASS 1004 202008 Block_3 60 FAIL 1004 202009 Block_3 82 PASS 1004 202009 Block_4 68 FAIL 1004 202010 Block_4 72 PASS 1004 202010 Block_5 90 PASS   This is my desired output: ID Class Training_Block Grade Status 1001 202001 Block_1 88 PASS 1001 202001 Block_2 76 PASS 1001 202001 Block_3 68 FAIL 1002 202004 Block_1 50 FAIL 1003 202003 Block_1 76 PASS 1003 202003 Block_2 89 PASS 1003 202003 Block_3 80 PASS 1003 202003 Block_4 95 PASS 1003 202003 Block_5 97 PASS 1004 202008 Block_1 74 PASS 1004 202008 Block_2 70 PASS 1004 202008 Block_3 60 FAIL   I feel like I've done this before and it involved do loops and first.dot and last.dot processing, but for the life of me I can't figure out how to do it this time.   Thanks in advance for help! ... View more