Analysis: Last year was a year of uncertainty and transition for privately held Air Wisconsin as the carrier lost its longtime contract with United and gained a contract to fly for US Airways. By all traffic measurements, it finished below the 2004 marks. It grew by at least 30 percent in 2004 over 2003.

Analysis: After growing by nearly 20 percent in traffic from 2003 to 2004, Comair slipped in 2005 to below 2004's benchmarks for traffic, capacity and load factor. December 2005 marked the beginning of a service cutback for Comair as part of the Delta bankruptcy; however, December 2004 includes the service breakdown over the Christmas holiday due to a weather-related computer crash.

Analysis: Delta Connection carriers grew by 50 percent in 2005 over 2004; however, a major element of that growth was the September sale of Atlantic Southeast Airlines from Delta to SkyWest. The ASA numbers for the last four months of 2005 are now part of the Delta Connection report.

Analysis: Era Aviation, which is now operating in Chapter 11, posted improved traffic numbers in 2005 over 2004 even as it dropped two Convair 580s last January. The airline did not replace the two planes but it still improved its capacity for the year.

Analysis: Even as Great Lakes now flies 198 daily flights to 40 airports compared to 160 flights to 31 airports a year ago, it is a smaller carrier. After growing its traffic by 7.7 percent in 2004 over 2003, it lost 12.1 percent of its traffic in 2005 over 2004.

Analysis: The pace of growth slowed in 2005 at Horizon Air compared to 2004. Last year marked the second complete year as a code-share partner with Frontier Airlines - it was this contract which fueled a 31 percent growth in traffic in 2004 over 2003.

Analysis: Jazz experienced blistering growth since July as it began to fly its new CRJ 705 fleet. While the slower first half held back its annual growth, Jazz's 50 percent traffic growth far surpasses the 4.9 percent growth rates posted in 2004 over 2003. In 2004, its capacity fell by 2.8 percent.

Analysis: In 2004, Mesa was the fastest growing regional as measured by traffic growth. In 2005, its near 18 percent growth fell far short of the 69 percent growth in traffic it recorded when Mesa rejoined the United family. In 2005, it expanded its United contract, added Delta, and is leaving US Airways.

Analysis: Mesaba's growth rate in 2005 was slower than in 2004, but its numbers really don't tell the story. Now in bankruptcy, Mesaba has had both Avros and Saabs pulled from its fleet in the last two months while in 2004 it spent almost six months rebuilding its Avro fleet after its near strike.

Analysis: Midwest Connect experienced its best year in terms of growth since 2003. While its traffic grew by 18 percent last year, it had no growth in 2004 over 2003. With essentially the same fleet, the carrier increased its capacity for the first time since 2002, but it is still 14,000 ASMs below that mark.

Analysis: Pinnacle reached its fleet peak in July 2005 at 139 CRJ 200s; however, due to the Northwest bankruptcy, the fleet has been cut to 124 since November. Its 2005 traffic growth rate at 42 percent fell short of the 61 percent set in 2004 over the 2003 mark.

Analysis: Republic continues to grow its fleet and expand its contract flying. In 2005, it grew by 47 percent compared to a 33 percent growth in traffic in 2004. It is now flying 47 Embraer 170s for US Airways, United and Delta compared to the 11 it had at the end of 2004.

Analysis: With its purchase of Atlantic Southeast Airlines, SkyWest was the fastest growing regional carrier in 2005. The ASA numbers of just four months propelled SkyWest with a 72 percent growth in traffic. In 2004, it grew traffic by 31 percent and capacity by 27 percent over 2003's benchmarks..

Analysis: For two years in a row, US Airways Express' in-house carriers grew traffic by more than 60 percent. In 2005, its capacity grew by more than 61 percent compared to the 40 percent capacity growth in 2004 over the 2003 tally. However, the pace of growth has slowed substantially since September 2005.

( ) Indicates corporate affiliation and operating units. { } indicates code-share partnerships.