The past week saw heavyweights in the airline space like American Airlines Group AAL, and Southwest Airlines Co. LUV revealing their traffic numbers for the month of March. As was the case in February, March traffic numbers from major carriers like JetBlue Airways Corporation JBLU saw a decline in load factor (% of seats filled with passengers) as capacity expansion outweighed growth in traffic.The traffic reports apart, United Continental Holdings’ UAL announcement of not proceeding with its previous plan to buy slots from Delta Air Lines DAL at the Newark Liberty International Airport, grabbed headlines. By virtue of this move, the Chicago-based carrier has called off efforts to expand its already strong position at Newark.Read the last Airline Stock Roundup for Apr 06, 2016.Recap of the Past Week’s Most Important Stories1. United Continental has retracted on its plans to expand further at the Newark Liberty International Airport, thereby vindicating the stance of the U.S. Justice Department. United Continental’s decision to call off its purchase agreement with Delta follows the Federal Aviation Administration’s decision, announced on Apr 1, 2016, to lift controls over the number of takeoffs/arrivals per hour at Newark (read more: United Continental to No Longer Buy Newark Slots from Delta).On a separate note, United Continental’s March traffic numbers were disappointing with all 3 important metrics viz. capacity, air traffic and load factor declining. Moreover, the carrier’s forecast with respect to passenger revenue per available seat mile (PRASM: a key measure of unit revenue) for the first quarter of 2016 is also disappointing (read more: United Airlines March Traffic Falls, Q1 PRASM Likely to Drop).2. Southwest Airlines announced strong traffic numbers for March 2016 with revenue passenger miles (RPMs: a measure of air traffic) improving 6.2% on a year-over-year basis to 10.9 billion. Available seat miles (ASMs: a measure of capacity) climbed 6.1% to 12.9 billion. The carrier still expects operating revenue per ASM (RASM: a key measure of unit revenue) to be flat on a year-over-year basis in the first quarter of 2016 (read more: Southwest Airlines March Traffic Up, RASM View Maintained).3. Traffic at American Airlines Group climbed 3.3% with capacity expanding 3.8%. Load factor declined 40 basis points to 81.7% in Mar 2016. The carrier expects PRASM to decline in the band of 7% to 8% in the first quarter of 2016 (read more American Airlines March Traffic Up, Q1 PRASM View Soft).4. In line with its efforts to better customer service, low-cost carrier JetBlue Airways announced that it intends to expand its premium “Mint” service to include key destinations along the West Coast.On the traffic front, the carrier announced a 12.1% increase in its March air traffic on a 12.5% capacity expansion. Load factor declined 40 basis points to 86.8% as capacity expansion outweighed traffic growth. March 2016 PRASM at the Long Island City, NY carrier declined approximately 7% on a year-over-year basis.5. As with most other carriers, load factor also declined at low-cost carrier Virgin America VA for March 2016. Capacity expansion was 15.1% and traffic growth was 14.6% for the month (read more: Virgin America March Traffic Soars, Load Factor Slips).PerformanceThe following table shows the price movement of the major airline players over the past week and during the last 6 months.CompanyPast WeekLast 6 monthsHA0.38%71.23%UAL-2.67%-5.64%GOL-3.10%-29.46%DAL-2.06%-2.30%JBLU-3.98%-22.79%AAL-0.43%-9.72%SAVE-2.29%-7.86%LUV2.31%9.38%VA0.29%68.11%ALK-0.83%7.21%The table above shows that almost all major airline stocks traded in the red over the past week with shares of GOL Linhas GOL declining the most (3.10%). The NYSE ARCA Airline index gained marginally over the past week to $91.34.Over the past six months, most airline stocks lost value. However, the NYSE ARCA Airline index gained 1.17% primarily on the back of strong gains at Virgin America (68.11%) and Hawaiian Holdings (71.23%).What's Next in the Airline Space?Delta Air Lines is scheduled to report its earnings numbers on Apr 14, kicking off the first quarter 2016 earnings season in the airline space. We expect the company’s earnings to be aided by low fuel costs as was the case in the last few quarters. Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report SOUTHWEST AIR (LUV): Free Stock Analysis Report JETBLUE AIRWAYS (JBLU): Free Stock Analysis Report GOL LINHAS-ADR (GOL): Free Stock Analysis Report DELTA AIR LINES (DAL): Free Stock Analysis Report UNITED CONT HLD (UAL): Free Stock Analysis Report AMER AIRLINES (AAL): Free Stock Analysis Report VIRGIN AMERICA (VA): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research