What it means
Environmental, social and governance factors, usually shortened to ESG, cover matters such as carbon emissions, employee treatment, supply chain standards, board oversight and business ethics. The index does not exclude whole sectors such as energy or mining.
Instead it uses a best-in-class approach, picking the strongest performers within each industry. Companies are scored through an annual assessment in which they answer detailed questions and provide evidence.
The score combines economic, environmental and social dimensions, with weights that differ by industry because the risks differ. Only the top-ranked group of a large starting universe is included, which is roughly the top tenth of the largest companies.
The index serves several purposes. Asset managers use it as a benchmark, product providers build funds and exchange-traded funds that track it, and companies use inclusion as a signal in their sustainability reports.
Many firms treat the assessment questionnaire as a useful checklist for improving their own practices. There are limits to what the index shows.
Scores rely partly on company disclosures, so firms that report more can sometimes score better than firms that do less reporting but behave well. Different ratings providers can also reach different conclusions about the same company, since there is no single agreed measure of sustainability.
Index membership is not permanent. Companies are reassessed every year, so a firm that suffers a major safety failure, a corruption scandal or a serious environmental incident can be removed.
This creates a practical incentive for managers to treat sustainability as an ongoing management task rather than a one-off project. For a finance professional, the main point is that sustainability is increasingly treated as a risk and cost topic, not only a moral one.
Poor environmental or governance practices can lead to fines, lawsuits, higher borrowing costs and damage to reputation. Investors who track an index like this are betting that good management of these risks supports long-term returns, though that is not guaranteed.
In practice
Real-world examples.
Example
A global manufacturer reduces its factory emissions by 30% and publishes audited data on worker safety. Its sustainability score improves, and it is added to the index. The investor relations team highlights this in its annual report to attract long-term shareholders, and it notes that the improvements also cut energy bills.
Example
A pension fund with $300,000,000 to invest sets aside part of its equity allocation for a sustainability-themed fund that tracks the index. The trustees want to reflect members' interest in responsible investing. They also compare the fund's returns with a standard global index each year to check whether the choice has cost members anything, and they report the result openly.
Example
A bank's credit committee notes that a borrower is a member of the index. It treats this as one of several positive signs on governance and risk management. The committee still bases its decision on cash flow and collateral.
Case study
Seen in the real world.
Greenfield Packaging is an illustrative, fictional manufacturer that received a request from several investors to explain its sustainability record. The finance director found that the company was not completing the annual assessments used by the main sustainability indices.
The company spent three months gathering data on energy use, waste, workforce safety and supplier standards, and it set targets to cut energy use by 15% over five years. Its score rose from below the industry median to just above it, which reassured two large shareholders that had written to the board.
Greenfield did not make the index in the first year but it won a lower interest margin on a sustainability-linked loan the following year. The board also found that the new data helped it spot wasteful energy use in two plants, saving about $400,000 a year. The illustrative lesson is that the discipline of measuring and reporting these factors can bring financial benefits even when the headline listing takes longer.
Watch out
Common mistakes.
- Assuming the index excludes all polluting industries, when it selects the best performers within every industry.
- Believing inclusion guarantees higher investment returns, when it only reflects a ranking of sustainability practices at a point in time.
- Treating ESG scores from different providers as interchangeable, when methods, weights and data sources differ, so the same company can rank very differently.
Questions
People also ask.
When was the index launched?
It was launched in 1999 and is widely seen as one of the first global sustainability benchmarks.
What does best-in-class mean?
It means selecting the companies that perform best on sustainability measures within their own industry, rather than excluding whole industries.
Can individuals invest in it?
You cannot buy the index itself, but funds and exchange-traded funds that track sustainability benchmarks are available, and their fees and holdings should be checked carefully before buying.
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