The value of mergers and acquisitions is supposed to hit an all-time high this year, with total deals reaching 4.614 trillion.Given below is a list of some top mergers and acquisitions in 2015.Pfizer Inc. and Allergan plc announced that their boards of directors have unanimously approved, and the companies have entered into, a merger agreement under which Pfizer, will combine with Allergan, in a stock transaction currently valued at $363.63 per Allergan share, for a total enterprise value of approximately $160 billion, based on the closing price of Pfizer common stock of $32.18 on November 20, 2015. The transaction represents more than a 30 percent premium based on Pfizer’s and Allergan’s unaffected share prices as of October 28, 2015. Allergan shareholders will receive 11.3 shares of the combined company for each of their Allergan shares, and Pfizer stockholders will receive one share of the combined company for each of their Pfizer shares.Charter Communications and announced on May 26 that it had secured a deal with the New York-based pay-TV operator. The deal values Time Warner Cable at $78.7 billion. Charter said it will provide $100.00 in cash and shares of a new public parent company equivalent to 0.5409 shares of CHTR for each Time Warner Cable share outstanding. The deal values each Time Warner Cable share at approximately $195.71 based on Charter’s market closing price on May 20, or approximately $200 based on Charter’s 60-trading day volume weighted average price.Dell Inc. and EMC Corporation announced they have signed a definitive agreement under which Dell, together with its owners, Michael S. Dell, founder, chairman and chief executive officer of Dell, MSD Partners and Silver Lake, the global leader in technology investing, will acquire EMC Corporation, while maintaining VMware as a publicly-traded company.Assuming, for illustrative purposes, a valuation for each share of tracking stock of $81.78, the intraday volume-weighted average price for VMware on Wednesday, October 7, 2015, EMC shareholders would receive a total combined consideration of $33.15 per EMC share and the total transaction would be valued at approximately $67 billion.Anthem, Inc. and Cigna Corporation announced that they have entered into a definitive agreement whereby Anthem will acquire all outstanding shares of Cigna in a cash and stock transaction and Cigna shareholders will receive $103.40 in cash and 0.5152 Anthem common shares for each Cigna common share. The total per share consideration equates to approximately$188.00 for each Cigna share based on Anthem's closing share price on May 28, 2015, valuing the transaction at $54.2 billion on an enterprise basis.Kraft Foods Group Inc. and H.J. Heinz Co. have agreed to join forces, creating one of the largest food companies in the world. The deal was driven by Heinz’s owners, Brazilian investment firm 3G Capital and Warren Buffett’s Berkshire Hathaway. The size of the deal is expected to be around $45 billion, one of the largest deals involving a private equity company on recordThe new company will have revenues of around $28 billion, according to the deal statement, with eight +$1 billion brands and five brands between $500 million-$1 billion, including the eponymous Heinz and Kraft, as well as Oscar Mayer, Ore-Ida and Philadelphia.The boards of directors of Berkshire Hathaway Inc. and Precision Castparts Corp.have unanimously approved a definitive agreement for Berkshire Hathaway to acquire, for $235 per share in cash, all outstanding PCC shares. The transaction is valued at approximately $37.2 billion, including outstanding PCC net debt. “I’ve admired PCC’s operation for a long time. For good reasons, it is the supplier of choice for the world’s aerospace industry, one of the largest sources of American exports. Berkshire’s Board of Directors is proud that PCC will be joining Berkshire,” said Warren E. Buffett, Berkshire Hathaway chairman and chief executive officer.Aetna and Humana Inc. announced on July 3 that they have entered into a definitive agreement under which Aetna will acquire all outstanding shares of Humana for a combination of cash and stock valued at $37 billion or approximately $230 per Humana share based on the closing price of Aetna common shares on July 2, 2015.In a news release, the companies said, “The complementary combination brings together Humana’s growing Medicare Advantage business with Aetna’s diversified portfolio and commercial capabilities to create a company serving the most seniors in the Medicare Advantage program and the second-largest managed care company in the United States. The combined entity will help drive better value and higher-quality health care by reducing administrative costs, leveraging best-in-breed practices from the two companies — including Humana’s chronic-care capabilities that measurably improve health outcomes for larger populations — and enabling the company to better compete with more cost effective products.”Avago Technologies Limited and Broadcom Corporation today announced that they have entered into a definitive agreement under which Avago will acquire Broadcom in a cash and stock transaction that values the combined company at $77 billion in enterprise value. Upon completion of the acquisition, the combined company will have the most diversified communications platform in the semiconductor industry, with combined annual revenues of approximately $15 billion. The deal valued Broadcom at $37 billion.Wells Fargo & Company announced today that it has signed an agreement to purchase GE Capital’s Commercial Distribution Finance and Vendor Finance platforms as well as a portion of its Corporate Finance business. The acquisition includes total assets of approximately $32 billion as well as businesses employing approximately 3,000 team members. The loan and lease portfolios are roughly 90 percent U.S.- and Canada-based. The transaction is expected to close in the first quarter of 2016.