Items are placed in the appendices in the order in which their references appear in the body of the report. Thus, the first appendix item called out in the report becomes Appendix 1 (or Appendix A), the next one mentioned is Appendix 2 (or Appendix B), etc.
Each item appearing in the appendices is referenced somewhere in the body of the report so that the reason for the item's inclusion may be clearly understood.