DARTMOUTH, MA: The great majority (82%) of privately owned companies in the US use at least one form of social media and, of those that do, LinkedIn remains the most popular although Instagram is gaining ground fast, according to a recent study.

Each year, the Center for Marketing Research at the University of Massachusetts Dartmouth examines social media usage among Inc. Magazine's top 500 companies, a list of the fastest growing, privately owned firms in the US.

The latest iteration of the academic study, which has been running since 2007, revealed that 94% of the Inc. 500 had a LinkedIn account in autumn 2016, when the researchers collected the data and conducted interviews.

Other popular social media platforms included Facebook (88%), Twitter (79%), Google+ (53%), YouTube (48%), Instagram (46%), and Pinterest (30%).

But the research found that usage of these platforms has not remained static over the past couple of years and, most notable, has been the rapid adoption of Instagram.

Usage of the photo-sharing site rose from 25% in 2014 to 32% in 2015 before jumping to 46% in 2016, making Instagram the fastest growing social media platform among the Inc. 500.

Meanwhile, Pinterest gained 1% since last year while YouTube fell 2% and Google+ saw a steep decline of 11%.

"The data appears to indicate a plateau with the use of major platforms. It may be that companies established their social media presence years ago and have made little movement in leaving platforms. The only notable change in the data is the dramatic growth of Instagram," the report stated.

That said, Facebook was found to be the platform with the most users, the biggest reach and the largest cultural impact. It also drove the largest share of social media referral traffic and had the highest conversion rate for e-commerce traffic.

Some 40% of executives cited Facebook as the most effective platform for their business, while also reporting that Twitter has become a less effective channel for sales growth.

Survey participants were also asked about the effectiveness of their social media efforts and the vast majority (94%) agreed that social media is effective in building brand awareness.

More than four-in-five (85%) said social media is effective in creating relationships with customers, while 81% believed that being active on social media is essential for business success.

However, when asked about their concerns, return on investment (59%) emerged as the biggest worry for businesses, followed by resources devoted to social media (52%), time allocation (52%), privacy issues (42%) and analytics (41%).

"The dramatic increase in the adoption of Instagram suggests that businesses are still exploring new platforms while holding onto all previous accounts," the report concluded.

"That coupled with reservations about the ROI of social media, points to a need to re-evaluate and possibly consolidate social media efforts."

Data sourced from University of Massachusetts Dartmouth; additional content by Warc staff