That's as simple as:
Code:
With ActiveDocument.Range.Find
.ClearFormatting
.Replacement.ClearFormatting
.Text = "([0-9])%(-[0-9])"
.Replacement.Text = "\1\2"
.Forward = True
.Format = False
.Wrap = wdFindContinue
.MatchWildCards = True
.Execute Replace:=wdReplaceAll
End With