Swords are the most widely equippable weapon type — most melee classes can carry one — which keeps demand broad across every level bracket.
Sword (Weapon)
Auction-house prices and price history for Sword in MoP Classic.
137 items in Weapons › Sword are currently auctionable in Mists of Pandaria Classic.
Prices refresh daily from TradeSkillMaster (TSM), so day-to-day gaps in lower-volume listings are expected rather than a collection problem.
Sword listings link to price-history pages with per-realm buyout, average, and median data for Mists of Pandaria Classic.