This excerpt taken from the XJT 8-K filed Jul 30, 2008.
Figure 4-8: Domestic Average Fare Premium: Legacy vs. LCC ($US)
Source: US DOT O&D Survey Q307
NB: Legacy includes AA, CO, DL, NW, UA and US/HP. LCC includes B6, F9, FL, NK ,SX, SY, TZ and WN (Regional Jets excluded)
While U.S. carriers domestic and Latin American yields finally began to increase in 2006, long-haul transoceanic yields continue to rise. As a result, several carriers, including Delta, Continental and United, are substantially increasing their transatlantic and transpacific capacity. This is likely to lead eventually to an erosion of yields in these markets as competition intensifies and capacity outstrips demand.