Users aren’t happy with social media. The American Customer Satisfaction Index (ACSI), which measures US customer satisfaction across multiple industries, released a report indicating that users are growing increasingly dissatisfied with social media platforms such as Facebook, Twitter and LinkedIn, which the organization names as having the least satisfied users.

The reason: the amount of advertising found on the platforms coupled with data privacy concerns.

According to “The ACSI E-Business Report 2018,” which surveys 5,169 consumers between July 18, 2017 and June 28, 2018, satisfaction with social media as a whole has dropped 1.4 percent down to a score of 72 on ACSI’s 100-point scale. This ranks social media among the bottom of the five industries the organization covers and the lowest of its three e-business categories, which includes internet news and search engines.

“Privacy concerns, bots and toxic online discourse have taken their toll on social media,” ACSI managing director David VanAmburg said in a statement, but those concerns are eclipsed by the number of ads users are presented with on these platforms.

He explains that even though data privacy remains an important topic for users, it’s “often in the back of their mind.” In terms of advertising, VanAmburg notes that “users don’t want to be inundated with ads while looking at pictures of their grandkids or watch a commercial before a YouTube video.”

Specifically, satisfaction with Facebook fell by one percent down to a score of 67, putting it near the bottom of the industry despite remaining as the largest social media platform in the world—a signal that user growth is slowing.

Facebook users ranked it as the worst when it comes to privacy protection, likely because of data scandals involving companies such as Cambridge Analytica, and the platform’s influence on the 2016 US Presidential Election. The social network has since been working to regain users’ trust by rooting out other potential privacy threats and working with Google, Microsoft and Twitter on a way to protect and transfer personal data between platforms. But most of all, users find advertisements on Facebook intrusive, with poor video and navigation speeds and stale content.

Similarly, the Facebook-owned photo-sharing platform Instagram saw a four percent drop to 72, driven largely by changes made to its order-feed algorithm, which haven’t been offset by feature upgrades such as Instagram stories. Despite being one of the most popular platforms for marketers, survey respondents said that the content doesn’t seem fresh, the site and video performance is poor, and the ads are too intrusive. However, the study does not take into account the recent implementation of IGTV, which could change things around for Instagram by letting users post longer videos.

Twitter saw a more severe drop in user satisfaction, falling four points to 66. Meanwhile, the Microsoft-owned LinkedIn platform gained two percent in rankings, tying it for last place alongside Twitter. Most other services including Tumblr remained static.

But not all social media platforms are doing poorly. Of the three services to gain points in the survey, Pinterest is named as the most satisfying social media platform, growing by three percent to 80. This makes for the second consecutive year the platform has improved, with its active user base doubling since 2015.

Unlike on most other social platforms, Pinterest users are more receptive to advertising. The report notes that even though most of the ads on Pinterest are content marketing-based, users state that it’s on par with Wikipedia, which has no ads.

The only other platform to see gains is YouTube, which rose one percent to a score of 75. Users enjoy the video streaming service’s speed and reliability, and they seem to have become accustomed to commercials appearing before their videos. It is unknown if subscription offerings such as YouTube Premium, which removes ads while providing access to additional content, will have a marked impact on user satisfaction going forward.