Information based on long term output indicators from the Wales Transport Strategy, which were grouped by their social, economic and environmental impacts for 2011.
Gwybodaeth yn seiliedig ar ddangosyddion allbwn yn y hir-dymor o Strategaeth Drafnidiaeth Cymru, a gafodd eu trefnu yn ôl eu heffeithiau cymdeithasol, economaidd ac amgylcheddol ar gyfer 2011.