GWI, Nielsen, Euromonitor and Milieu market their audience data by giving some of it away. In SOMIN's analysis of 1,682 organic posts published between 18 October 2025 and 17 October 2026, 70% were thought leadership built on each firm's own findings, from Nielsen's streaming charts to Euromonitor's category rankings. Their paid ads tell a different story: most of them sell a product or recruit the survey panellists the data depends on.
Key takeaways
- Each feed is a sample of the data behind it: Nielsen posts about pop culture, sports and media, Euromonitor about retail and finance, GWI about business, technology and marketing, and Milieu about Southeast Asian consumers.
- Milieu posts most often, about 13 times a week, while Nielsen earns the most engagement per post: 71 on average, against 14 for Milieu.
- Posts about people, such as leadership appointments, averaged 104 engagements across the four firms, three times the overall average of 34.
- In paid media, 211 of Nielsen's 240 ads recruited members for its panels, app or surveys, and 120 of GWI's 124 ads targeted business buyers.
- Panels and social data answer different questions, so a buyer should ask every vendor where its numbers come from and how they can be checked.
How did we run the study?
We pulled every organic post from the four firms' channels connected to SOMIN's audience-research workspace, using the SOMIN platform, for the 12 months from 18 October 2025 to 17 October 2026. That gave 1,682 posts: 692 from Milieu, 387 from Nielsen, 304 from GWI and 299 from Euromonitor. We also pulled the 456 paid ads captured for the same firms and period, 441 of them on Meta placements. SOMIN's own posts sit in the same workspace and are left out of every figure here.
SOMIN's models tag each post with topics, content types, tones and formats. A post can carry several tags, so shares can add up to more than 100%. Engagement means reactions, comments and shares. We did not collect follower counts, so engagement per post reflects the size of each audience as much as the quality of the content. Euromonitor's posts in the workspace come from LinkedIn only. We ran the same kind of study on 18 vendors in what social listening tools post about.
How much do they post, and where?
| Firm | Organic posts (12 months) | Posts per week | Channel mix | Average engagement per post |
|---|---|---|---|---|
| Milieu | 692 | 13.3 | LinkedIn 41%, Facebook 31%, Instagram 28% | 14 |
| Nielsen | 387 | 7.4 | LinkedIn 55%, Facebook 26%, Instagram 18%, TikTok 1% | 71 |
| GWI | 304 | 5.8 | LinkedIn 65%, Instagram 28%, TikTok 5%, Facebook 2% | 29 |
| Euromonitor | 299 | 5.7 | LinkedIn 100% | 34 |
LinkedIn carries most of the volume for all four, which fits a business-to-business product. The bigger differences sit off LinkedIn. Nielsen's 69 Instagram posts averaged 141 engagements, almost twice its LinkedIn average of 75. GWI's 16 TikTok videos averaged 155, against 24 on LinkedIn. Milieu's Facebook posts averaged 31, three times its LinkedIn figure.
Cadence shifted during the year. In the last quarter of the window (18 July to 17 October 2026), Euromonitor published 37 posts, down from 92 in the quarter before, and GWI published 46, down from 83. Nielsen moved the other way, from 55 posts in the January to April quarter to 130 in the latest one.
What topics does each firm lead with?
Each feed reads like a trailer for the firm's data. The topic labels below are SOMIN's classifications, with the share of each firm's posts that carry them.
- Nielsen leads with Pop Culture (58%), Sports (47%) and Media (34%): streaming charts, NFL and broadcast ratings, horror-series viewing and the K-content wave. It markets measurement by showing what people watch.
- Euromonitor leads with Retail (75%), Finance (64%) and Business (54%): category rankings, Europe's top FMCG e-commerce brands and its record in economic forecasting awards.
- GWI spreads across Business and Technology (47% each), Pop Culture (44%), Career (41%) and Marketing (39%). It also leans hardest into artificial intelligence: its 23 posts tagged with an AI topic averaged 83 engagements, against 29 for GWI overall.
- Milieu leads with Finance (41%), Business (28%) and Technology (25%), framed around Southeast Asia: Thai online shoppers, Ramadan in Malaysia and Indonesia, 11.11 sales and six regional shopper types.
Thought leadership dominates three of the four feeds: 93% of Nielsen's posts, 92% of Euromonitor's and 83% of GWI's. Milieu is the exception at 42%, with more brand offering (64%), topical posts (46%) and community engagement (31%), such as polls that ask followers what makes them buy.
Which formats and tones do they use?
| Firm | Image / carousel / video share | Best format by average engagement | Most common tones |
|---|---|---|---|
| Milieu | 52% / 45% / 1% | Single image (21) | Informative 77%, informal 31% |
| Nielsen | 31% / 41% / 26% | Single image (110) | Informative 90%, authoritative 73% |
| GWI | 20% / 46% / 31% | Video (49) | Informative 76%, informal 50% |
| Euromonitor | 37% / 22% / 30% | Single image (40) | Informative 81%, authoritative 72% |
Carousels are the default way to package a dataset, yet they rarely won. Milieu's 313 carousels averaged 7 engagements, against 21 for its single images. GWI's 139 carousels averaged 18, against 49 for its videos. Nielsen's single-image posts averaged 110, the highest format average in the study.
Tone splits the group in two. Nielsen and Euromonitor write in an informative, authoritative register in roughly three posts out of four. GWI is informal in half of its posts and Milieu in almost a third. Nielsen's 43 informal posts averaged 126 engagements, against its overall 71, a hint that its audience does not insist on formality.
What gets the most engagement?
Three patterns stand out in the posts that drew the most response.
- People beat data. The 70 posts tagged Company Culture, such as leadership appointments and team events, averaged 104 engagements, three times the overall average. Nielsen's 13 such posts averaged 379, and its single most engaged post of the year announced a new Chief Client Officer. Educational explainers averaged 23.
- Culture beats category. Nielsen's strongest content rides on what audiences already follow: women's sports, streaming charts, the NFL. Milieu's top post of the year was a bilingual Thai and English Facebook poll asking shoppers what makes them buy straight away, which drew almost 2,500 reactions.
- Clients' claims travel. Three of Euromonitor's eight most engaged posts were reshares of clients announcing a ranking from Euromonitor International: AESTURA in Korean dermocosmetics, Dreame in premium robot vacuums and Jollibee in Southeast Asian chicken restaurants. Claims of this kind are also a product: Euromonitor's claim-validation team certifies statements such as market share leader or best-selling, and each certificate is valid for 12 months.
How does their paid advertising differ from their organic posts?
The organic feeds sell expertise; the ads sell products and recruit respondents. Only 21% of the 456 ads were tagged as thought leadership, against 70% of organic posts.
- Nielsen ran 240 ads, and 211 of them (88%) promoted the Nielsen Computer & Mobile Panel, the Nielsen Pulse app or Nielsen surveys, offering rewards to people who let Nielsen measure their browsing, streaming or screen time.
- GWI ran 124 ads, 120 of them aimed at businesses. A third (41) promoted Agent Spark, which brings GWI's survey data into AI assistants and is positioned against web-scraped content. Another 34 promoted a social media audience report.
- Milieu ran 92 ads. Of these, 29 recruited members for its survey app, and others, including Thai-language ads, offered demos of its research tools.
- Euromonitor had no ads captured in the period.
A survey panel has to market on two sides at once: to the companies that buy the data and to the people who supply it. Nielsen's paid media is almost entirely the second kind.
What does this tell a buyer of audience research?
Read a vendor's feed as a free sample of its data, then ask the questions the feed cannot answer.
- What is the data best at? The topics a firm posts about are usually where its data is deepest: media for Nielsen, retail categories for Euromonitor, digital consumers for GWI, Southeast Asia for Milieu.
- Who answers, and why? Panels reward their members: Nielsen's panel FAQ describes points and sweepstakes, and Milieu's survey app gives points that members redeem for rewards. Incentives are normal, but they can also draw in people who want the reward more than they want to answer carefully. Pew Research Center found that in opt-in online polls, 12% of respondents under 30 claimed a licence to operate a nuclear submarine, a share that in reality rounds to zero. Ask how a vendor recruits, rewards and screens its panel.
- Is it stated or observed? A survey records what people say they do. A meter, a receipt or a social post records what they did or said unprompted. Many vendors blend both: Euromonitor's methodology combines trade and company sources, store audits, trade interviews and surveys with e-receipts and web-scraped product data.
- How current is it? GWI Core has run in quarterly waves since 2013, and a Euromonitor claim certificate lasts a year. Check the fieldwork date behind any chart.
- Can you trace a number back to its source? This matters most when an AI tool sits between you and the data. We cover how to check that in why marketers distrust AI insights.
How is social-data audience research different from panel and survey research?
Panel and survey research asks a defined sample of people questions and weights the answers to represent a population. Social-data research, which is what SOMIN does, reads what brands and people have already published and works out who it speaks to, which tensions it carries and what performs. The two answer different questions.
| Dimension | Panel and survey research | Social-data audience research |
|---|---|---|
| What it captures | Stated attitudes and reported or metered behaviour | Published content and the response to it |
| Who is in the data | A recruited, usually rewarded sample, weighted to a population | Brands, creators and the people who engage with them |
| Speed | Fieldwork waves, often monthly or quarterly | Continuous, as posts and ads appear |
| Main strength | Sizing and representativeness | Competitor coverage, creative evidence and unprompted language |
| Main risk | Inattentive or bogus respondents, question wording | Not representative, because active posters dominate |
| Best for | How many people, which segments, how big a market | What the market says, what works and where the gaps are |
The representativeness gap is real. Pew Research Center found that the most active 10% of US adult Twitter users produced 80% of the tweets from US adults, and that users were younger and more educated than the public. Social data shows what is being said and what lands, not what a whole population thinks.
The methods work best together: social data to find the tension, the angle and the gap in a category, then a panel to size the audience that feels it. For a side-by-side of the tool categories, see social listening vs audience research vs ad optimisation. SOMIN Strategy shows how we turn published content into personas and tensions, and our social media benchmarks page puts these engagement figures in context.
FAQ
How often do GWI, Nielsen, Euromonitor and Milieu post on social media?
Between 18 October 2025 and 17 October 2026, Milieu averaged about 13 organic posts a week, Nielsen about 7, and GWI and Euromonitor about 6 each. The counts cover the channels connected in SOMIN's audience-research workspace; Euromonitor's are LinkedIn only.
Which audience research firm gets the most social media engagement?
Nielsen, with 71 engagements per post on average, followed by Euromonitor (34), GWI (29) and Milieu (14). These figures are not adjusted for follower counts, so they reflect audience size as well as content.
Why do research firms run ads that offer rewards?
Panel-based research needs a steady supply of respondents. Most of Nielsen's ads in our data recruit members for its Computer & Mobile Panel, Pulse app or surveys, and about a third of Milieu's ads recruit for its survey app.
Is social media data a substitute for survey research?
No. Social data is unprompted and fast, but the people who post are not a representative sample. Use it to find tensions, messages and gaps, and use a survey or panel when you need to size an audience.
How was this data collected?
With the SOMIN platform, from the organic posts and paid ads of the four firms connected in its audience-research workspace, dated 18 October 2025 to 17 October 2026. Topics, content types, tones and formats are model-generated tags, and a post can carry several.
Sources
- Pew Research Center: Online opt-in polls can produce misleading results, especially for young people and Hispanic adults (2024)
- Pew Research Center: Sizing up Twitter users (2019)
- GWI: Understanding GWI Core
- Nielsen: Computer & Mobile Panel FAQ
- Euromonitor International: Research methodology
- Euromonitor International: Validate marketing claims
- Milieu Insight: Milieu Surveys community
