Global merger and acquisition (M&A) deal volume reached $2.3 trillion so far this year, registering an increase of 9 per cent from last year levels, Dealogic said in a report today.  According to the global deal tracking firm, global M&A volume has reached $2.30 trillion in 2013 year-to-date, up 9 per cent from the $2.10 trillion in the corresponding period last year.  The M&A deal volume of $2.3 billion so far this year was the highest year-to-date total since 2008, when deals worth $2.77 trillion were announced.  "The M&A deal volume this year was mainly driven by Verizon Communications' $130.0 billion bid for a 45 per cent stake of Verizon Wireless announced on September 1," Dealogic said.  The deal also marks as the second largest M&A deal on record, behind Vodafone AirTouch's $172 billion transaction for Mannesmann in 1999, it added.  In sharp contrast, deal activity has dropped to 29,813 transactions in 2013 year-to-date, down 16 per cent over the corresponding period of last year when 35,577 transactions were announced.  A sector-wise analysis shows that the Telecom sector, with deals totalling $329.9 billion, was at the top in the list for global M&A so far this year, followed closely by real estate and healthcare with $284.5 billion and $240.1 billion, respectively.  In terms of global M&A advisor ranking, Goldman Sachs topped the chart with $626.5 billion, followed by JPMorgan and Morgan Stanley with $603.7 billion and $515.8 billion, respectively, Dealogic said.