STAMFORD, CT -- Worldwide semiconductor revenue totaled $334.8 billion in 2015, down 2.3% year-over-year, says Gartner.

The combined revenue of the top 25 semiconductor vendors fell by 0.5% during 2015. This was better performance than the rest of the market, however, which saw a 6.9% revenue decline, the firm says. The top 25 vendors accounted for 73.5% of the market, down from 74% in 2014.

"The worldwide semiconductor market declined in 2015 as slowing demand for key applications combined with strong currency fluctuations to subdue the market," said Andrew Norwood, research vice president at Gartner. "2015 saw a mixed performance by the different device categories, unlike 2014 when all categories posted positive growth. Non-optical sensors performed best due to increased usage of fingerprint sensors in smartphones, while discretes saw the strongest decline due to a mix of weak demand and currency issues."

Intel retained the No. 1 market share position for the 24th consecutive year, capturing 15.4% of the worldwide market, despite experiencing a 1.2% revenue decline in 2015. Infineon Technologies experienced the strongest growth among the top vendors, moving from No. 12 to the No. 9 position in 2015.

2015 saw record merger and acquisition activity between major semiconductor vendors, including several acquisitions and disposals that had a material effect on semiconductor sales. Among the most significant deals was Intel's acquisition of Lantiq, says Gartner. Driven by Lantiq's broadband gateway and digital home capabilities, this acquisition helped Intel nearly double its wired ASSP business.

"2015 semiconductor revenue results are skewed by the large amount of M&A activity during the year," said Norwood. "If we adjust for this M&A activity by adding in revenue for 2015 and 2014 where necessary, then the performance is somewhat different. The top 25 vendors would have experienced a 1.7% revenue decline, and the rest of the market would have declined 3.9%."