In the VBA for modelers 4th edetion, chapter 26 problem 1E, step 7, my code is totalNPVOpt(tollndex) = Range("TotNPV"), but an error appears saying that it was supposed to be a matrix in there. Can anyone help me please?

Edit: This is the sub that i'm working on

Sub RunSolver(tollndex As Integer)

Dim tolerance As Single, i As Integer If tollndex = 0 Then tolerance = 0 Else tolerance = 5 End If With wsModel SolverReset SolverOK SetCell:=.Range("TotNPV"), MaxMinVal:=1, ByChange:=.Range("InvLevel") SolverOptions IntTolerance:=tolerance, AssumeLinear:=True SolverAdd CellRef:=.Range("TotCost"), Relation:=1, FormulaText:="Budget" SolverAdd CellRef:=.Range("InvLevel"), Relation:=5 SolverSolve UserFinish:=True For i = 1 To nProjects zeroOne(tollndex, i) = Range("Invlevel").Cells(i) Next totalNPVOpt(tollndex) = Range("TotNPV") leftoverOpt(tollndex) = Range("Budget") - Range("TotCost") End Sub