Overall, 198 deals were reported in the first half of 2016, only slightly lower than 199 in the first half of 2015.

Deal value, however, dropped significantly, from $159 billion to $86 billion.

"In short, the expected surge in consolidation and M&A activity has yet to materialise," according to the report.

"Surprisingly, deal activity during the last recession was more robust than it has been in the last two years."

Deloitte