We have requested that the SAM grader be modified to accept the @ in a structured reference, and that change will be coming soon. BUT for now be sure you select the structured references for the formulas in Excel Case 8 by selecting the FIELD (black arrow pointing down at the top of the column field name - do NOT click the individual cell in the row).
If you click in the cells (like F2) in the row of the formula to create the formulas, it creates a structured reference like [@[Service Years]]. The SAM 2016 grader is currently marking every formula with @ as incorrect; they want you to click on the column header to select the field so it reads the structured reference like [Service Years].
Step 4 - Should have a POSITIVE value, so it should be 2018-First Aid Certification Year
the instructions SHOULD be switched to say subtract the value shows in the 2018 field FROM the First Aid Certification Year column.
Thank you for your patience as we continue to send feedback to the SAM team about the new 2016 content.
K201 Course Coordinator