GeologicTimescale

Numbers refer to end of time period, in millions of years before now. Is there a better way to format this?

    *  CenozoicEra?
         NeogenePeriod?
   23    PalaeogenePeriod?
   65  MesozoicEra?
        CretaceousPeriod?
  146    JurassicPeriod?
  208    TriassicPeriod?
  245  PalaeozoicEra?
         PermianPeriod?
  290    CarboniferousPeriod?
  363    DevonianPeriod?
  409    SilurianPeriod?
  439    OrdovicianPeriod?
  510    CambrianPeriod?
  570  PrecambrianEra?