e by acceleration to reach APPENDIX A: The Argument in Notation 3/7/16 18 HOUSE_OVERSIGHT_011144 dr of anit die ffi am Aen, (A9.2) dg dg dtdg dtdg g g Ag Ag drK, or Ark, give free growth as a flow, while —dfK, or —AdfK,, give the flow of thrift. Define the “productivity index” or “free growth index” @