Since 2008, the aerospace industry has experienced a slowdown in growth due to reduced global military spending. Aerospace companies that rely more heavily on defense contracts have seen revenues fall or flatten as defense departments and ministries of defense shift procurement activities away from defense contractors and toward technology companies. These companies are in search of lower-cost digital solutions for other military functions, such as intelligence gathering, surveillance and communications.

The tide may change later in 2016 and beyond, as increased global security threats force countries, including the United States, to upgrade their weapons and security platforms. Low oil prices and stable gross national product growth across the globe will continue to fuel commercial aerospace revenue, as aircraft manufacturers gear up for the production of next-generation aircraft. All of this has resulted in a jockeying of positions for the world’s top aerospace companies, as revenues ebb and flow in the shifting defense landscape.

Boeing Co.

The Boeing Co. (NYSE: BA) generated $96.1 billion of revenue in 2015, with only 32% coming from defense contracts. With commercial and government customers in 150 countries, the Chicago-based company is one of the top manufacturers of commercial airliners and military aircraft. It is also heavily involved in advanced technology solutions for defense, space and national security. Its overall revenue was up 6% over the prior year, but its operating margins have been shrinking. For 2016, Boeing is forecasting lower earnings growth due to fewer shipments of airplanes, and lower production due to weaker demand.

Airbus Group SE

With $70.14 billion in revenue, Airbus Group SE (OTC: EADSY) is one of the largest aerospace and defense companies in the world. However, just 18.10% of its revenue comes from defense contracts. Based in the Netherlands, Airbus Group SE manufactures passenger aircraft, corporate jets and cargo aircraft. For its military customers, the company makes military transport and special mission aircraft. Its 2015 revenue increased by 6.2%, as did its net margin, from 3.9 to 4.2%. Coming off of several years of increasing profits, the company expects continued earnings growth in 2016, with higher plane shipments than the prior year.

United Technologies Corporation

Of the $56.09 billion of revenue generated by United Technologies Corporation (NYSE: UTX) in 2015, 20%, or $13 billion, came from defense contracts. Through its Pratt & Whitney aerospace division, the company provides aircraft engines for the military and general aviation industry. It also provides repair and maintenance services. Both its revenue and operating margins fell in 2015, and the company expects flat to slightly higher earnings in 2016.

Lockheed Martin Corporation

At $46.13 billion in annual revenue in 2015, Lockheed Martin Corporation (NYSE: LMT) experienced just 1.2% in revenue growth over the prior year. Lockheed Martin is the largest defense contractor in terms of revenue, generating $40.13 billion in 2015. Its product portfolio includes military aircraft, vehicles, missiles, unmanned systems, radar systems and guided weapons. Due largely to its F-35 program and increased shipments of C-130 cargo planes, Lockheed expects slightly higher revenue and earnings in 2016.

Honeywell International Inc.

Honeywell International Inc. (NYSE: HON) is a diversified manufacturer of commercial and consumer products, including avionics, engine systems, transportation systems, aircraft wheel and brake repair, environmental control systems, and radar and surveillance systems. Its annual revenue in 2015 was $38.58 billion, of which $4.75 billion came from defense business. Revenue was down 4.3% while its operating margin increased 2.7%, to 14.1%. The company expects revenue to increase in 2016, reaching $40 billion, with a 6% increase in earnings.

General Dynamics Corporation

General Dynamics Corporation (NYSE: GD) generates 60.2% of its $31.47 billion annual revenue from military contracts. In addition to combat vehicles, shipbuilding, communication technology systems, weapons systems and munitions, the company is a major player in business aviation. General Dynamics managed a small increase of 2% in its revenue over 2014, while also increasing its operating and net margins by around 10%. Weaker demand for business jets has led the company to project lower revenue in 2016, but improved profit margins are expected to boost earnings to a higher level than expected.

BAE Systems Plc.

BAE Systems plc (BA.L) is a London-based manufacturer of naval ships, submarines, military aircraft, guided weapons systems and space systems, with customers throughout the world. The company reported revenue of $25.45 billion in 2015, of which 92.80% is from defense contracts. That is an 8.8% increase over 2014. Due to fewer orders and the loss of some key contracts, the company was forced to lower its earnings estimates for 2016.