I need help to multiply a column with values by 180% & then ROUNDUP to 1 decimal

One way

Sub test()
    With Range("h1", Range("h" & Rows.Count).End(xlUp))
        .Value = Evaluate("if(" & .Address & "<>"""",if(isnumber(" & _
        .Address & "),round(" & .Address & "*1.8,1)," & .Address & "),"""")")
    End With
End Sub