1. What the Sentiment Index measures
The Sentiment Index ranks companies on the tone of the news about their sustainability record. It measures how others see a company, not how the company communicates: that is what the Sustainability Reporting Index and the Sustainability Website Index measure. It does not measure emissions, targets or performance, and a higher rank does not mean a company is more sustainable.
2. Which news counts
- News about the company. We collect news about each company from Financial Modeling Prep, WorldNewsAPI, NewsData.io, GNews and Currents.
- Sustainability news only. Each article is classified once, when we store it, as sustainability news or not. Only sustainability news counts (section 3).
- Articles in English. Sentiment is scored in English only. Articles in other languages are stored without a score and do not count.
3. How an article counts as sustainability news
Each article is checked once, when we store it, in three steps.
- Is the company in the article? Our own AI model checks that the article names or clearly refers to the company, one of its businesses or one of its brands. A shared name is not enough: a story about the city of Zurich is not about Zurich Insurance Group.
- Does the article use sustainability language? It must contain at least one keyword from our environmental, social and governance themes. The same keywords file the article under its themes.
- Is the company linked to a sustainability theme in the article? Our AI model checks that the article ties one of our themes to the company itself: for example emissions and climate, pollution and spills, worker safety, pay and diversity, community impact, board oversight and ethics. A company mentioned beside a theme that is about others does not count.
An article counts only when all three are yes. How sure the model must be is set by testing it against articles checked by hand. If the model can't be reached, no new articles are stored until it can.
4. How sentiment is scored
Each article's headline and summary are scored with VADER, a widely used rule-based sentiment tool for English. It gives three shares, positive, neutral and negative, which add up to 100%, and a compound score from -1 (most negative) to +1 (most positive).
For each company and period we report:
- Sustainability articles: how many articles counted.
- Average sentiment: the mean compound score. This is what ranks the company.
- Positive share and negative share: the mean positive and negative shares, which the chart plots.
- The middle half: the range the middle 50% of the company's articles scored, shown when you hover over a company.
Each sector page describes the sector's ranked companies over the last 12 months, with no company named. It counts a company's news as positive when its average sentiment is 0.05 or more, negative at -0.05 or less, and neutral in between, the usual VADER cut-offs.
5. How a rank is computed
- Companies are ranked within their sector by average sentiment, highest first. Ties go to the company with more articles, then by name.
- Every company counts equally. The rank uses the average, not the total, so a company in fewer stories is not ranked below one in many.
- At least 5 articles. A company with fewer than 5 sustainability articles in the period is shown without a rank, with the reason.
- Sectors are the 11 standard sectors of the Reporting Index. A company whose sector and industry are not a standard pair shows Sector not classified. Clients are left out by the same rule as the Reporting Index.
6. Periods
The default is the last 12 months. You can also choose the last 6 or 3 months, or a calendar year. Each period is ranked on its own.
7. What a visitor can open
The same rules as the Reporting Index. Without a link or an account, the page shows how many companies rank in each sector, with no company names or scores. A link from us or a free work account opens one sector: the chart and the first 50 rows. Plus opens every page of the subscriber's own sector, and Max opens every sector. The page shows scores and counts only, never the articles themselves.
8. Limitations
- Tone is not truth. VADER reads words, not facts. A story about a company fixing a problem can score negative, and sarcasm or quotes can mislead it.
- Coverage varies. Large companies are in more news than small ones, and the sources above don't cover every outlet. The average treats companies equally, but a company with 5 articles has a less settled score than one with 500.
- Headline and summary only. We score what the providers give us, not the full article.
- English only, as above.
9. Refresh and corrections
Rankings are recalculated every night from the news we hold, and the page shows when they were last updated. If a company or its news is wrong, use the form on the Sustainability Reporting Index page and say it is about the Sentiment Index.