Worldwide corporate merger activity hits record level

Companies around the world made plans to spend a record $5.04 trillion on acquisitions in 2015, according to Dealogic, as slow worldwide economic growth and low interest rates pushed companies to combine forces.

Dealogic, a financial data provider, said the value of announced global deals soared 37 percent in 2015. The highest price tag came in November, when Pfizer and Allergan announced the biggest pharmaceutical deal in history.

The record-setting volume in 2015 breaks the previous record of $4.6 trillion set in 2007, by 9 percent.

Low interest rates since the Great Recession have made it cheaper for companies to borrow money to pay for acquisitions, and because the global economy only grew slowly this year, companies decided it made more sense to buy their competitors instead of trying to boost their sales on their own.

Here are the 10 largest acquisitions announced during the year:

Pfizer and Allergan

Pfizer, the maker of cholesterol fighter Lipitor, impotence treatment Viagra and fibromyalgia drug Lyrica, agreed to buy Allergan in November. The $148.57 billion deal would be the second-largest corporate merger ever. It would give Pfizer control of Botox and move the company's headquarters to Ireland, cutting its taxes. Pfizer would also become the world's largest drugmaker in terms of sales.

AB InBev and SABMiller

The biggest beer maker in the world wants to get even larger. The company behind Budweiser, Corona and Stella Artois agreed to buy the maker of Miller Genuine Draft and Peroni for $105.56 billion in October. The move would expand AB InBev's business in Africa, Asia and other key developing markets. As part of the deal, SABMiller agreed to sell the Miller brand to Molson Coors.

Royal Dutch Shell and BG Group

When Royal Dutch Shell agreed to buy BG Group in April, oil prices had taken a steep fall from their 2014 highs. But they were going to get a lot worse. Oil and gas company Shell agreed to buy BG Group for $69.83 billion to expand its liquid natural gas business. Natural gas prices have tumbled since then, and in December they reached their lowest levels in 16 years.

Dell and EMC

In October PC maker Dell agreed to pay $65.97 billion for EMC, which makes data storage hardware and sells cloud storage and security products. Dell's personal computer sales have been weak for years, but the company has been expanding its software and service businesses. Dell was taken private in 2013 by founder and CEO Michael Dell.

Dow Chemical and DuPont

Dow Chemical agreed to buy competitor DuPont in a deal that will combine two chemicals companies that were founded in the 19th century. Both Dow and DuPont were pushed by activist investors to break up or find other ways to revitalize their businesses. When the $62.38 billion deal closes, Dow DuPont will make products including Ziploc bags, Saran wrap, Teflon coatings and Nylon and Kevlar fibers. Dow DuPont will then break into three separate companies with more specific focuses.

The deal has potential implications for Dow subsidiary Dow AgroSciences, which is headquartered in Indianapolis, where it has about 1,500 employees.

Charter Communications and Time Warner Cable

Charter Communications agreed to buy Time Warner Cable for $56.80 billion in May, and it will also spend about $10 billion to buy Bright House Networks. That will make Charter one of the largest providers of TV and internet services in the U.S. Cable provider Comcast tried to buy Time Warner in 2014, but the U.S. government opposed that deal.

Heinz and Kraft Foods

One of the largest food companies in the world was formed when H.J. Heinz bought Kraft Foods for $53.83 billion. The purchase, which was announced in March and closed in July, brought together brands including Oscar Meyer, Capri Sun, Ore-Ida, Maxwell House, Kool-Aid and Heinz ketchup. The tie-up was engineered by Warren Buffett's conglomerate Berkshire Hathaway and Brazilian investment firm 3G Capital.

Anthem buys Cigna

A wave of health insurance combinations swept the market in July as Indianapolis-based Anthem announced it would buy Cigna for $51.93 billion just after Aetna said it would buy Humana for $35.04 billion. Anthem is the second-largest U.S. insurance company in terms of enrollment, and Cigna is fourth. The combined company would cover almost 50 million people. Anthem sells health coverage to individuals and employees of small businesses and serves Medicare, Medicaid and federal employees. Cigna sells group disability and life insurance in the U.S. and has an international business.

EBay spins off PayPal

Online commerce giant EBay spun off its payments system unit PayPal for $49.16 billion in July. That was almost a year after eBay announced PayPal would become a separate company. Investors value PayPal more highly than its former parent, as PayPal has a market capitalization of about $45 billion compared to eBay's $33 billion.

Teva buying Allergan Generics

Teva, an Israeli company that is already the world's largest manufacturer of generic drugs, will get even bigger by buying the generic drugs business of Botox maker Allergan. Teva had been looking to expand, as earlier in the year it pushed to buy generic drugmaker Mylan. It dropped that bid after agreeing to its $40.5 billion deal with Allergan.