Venture capital investing reached a fever pitch in 2015, setting an all-time high. Don't look for that to continue in 2016.

Investor sentiment shifted dramatically in the fourth quarter of last year, according to venture capital researcher CB Insights, which released its fourth-quarter report on global venture capital financing on Tuesday. CB Insights produced the report with the consultancy KPMG.

The findings correlate with an uneven year for business in 2015, due to stock market volatility in the third quarter, which ended a long bull run in the wake of weakening global economies and a devaluing of China's currency. The Federal Reserve Board's decision to increase its benchmark interest rate during the quarter also appears to have muted some late-stage investment prospects, according to some investment experts. And a host of hyper-valued companies had their valuations decreased by institutional investors during Q4.

"There's a mentality of hunker down and hold onto cash," Francois Chadwick, national tax leader at the KPMG Venture Capital Practice, says in the report. "There is an immediate expectation that as interest rates go up, investors can find greater return on capital by investing it in lower-risk portfolios."

Globally, venture capitalists invested a record $128.5 billion in 2015, an increase of 44 percent compared with the previous year, according to the report. Yet funding worldwide in the fourth quarter of 2015 fell by 30 percent from the prior quarter, to $27 billion, while the number of deals fell 13 percent, to 1,742 over that period.

Here are six takeaways from the report.

1. The U.S. leads VC funding

U.S. companies received the lion's share of investment in 2015, with $72.4 billion in deals. Funding in the fourth quarter of the year fell 32 percent from the third quarter, to $13.8 billion, however. The number of U.S. deals fell by close to 200 over the same time period, to 981.

2. Trouble for startups

Startups looking for seed funding in 2016 may have some trouble. Globally, early-stage rounds accounted for 29 percent of funding in the fourth quarter, a decline of five percentage points from the fourth quarter of 2014. In the U.S., seed funding accounted for 24 percent of all Q4 funding, a five-quarter low.

3. An end to mega-deals?

Financings worth $100 million or more fell by almost half in the fourth quarter of 2015, to 38 worldwide, compared with the third quarter. In the U.S. in Q4, such deals fell by more than 50 percent, to 18, compared with Q3.

4. The death of new unicorns

The number of newly minted unicorns--companies valued at $1 billion or more--dropped to 12 worldwide in the fourth quarter of 2015, with seven of those in the U.S. That's compared with 24 new unicorns in the third quarter of 2015, including 17 in the U.S.

5. Most active VCs

The most active venture capital firms in North America during 2015 were New Enterprise Associates, General Catalyst Partners, Andreessen Horowitz, Kleiner Perkins Caufield & Byers, Greycroft Partners, and Khosla Ventures.

6. Most active states

The biggest states for venture capital activity were California, Massachusetts, and New York, which together accounted for more than half of all U.S. venture funding in the fourth quarter of 2015.