Bloomberg Barclays MSCI Green Bond Index was voted best index for the third consecutive year.

The index has an important role in the market, because it vets issues that fail to meet its green criteria, or do not uphold their green promise.

Self-labelled green bonds are evaluated by MSCI's ESG researchers against an independent methodology, verifying that the use of proceeds fall within one of seven categories: alternative energy, energy efficiency, pollution prevention & control, sustainable water, climate adaptation, green building and others.

Additionally, issuers must outline a process for project evaluation, management of proceeds and ongoing reporting.

For example, the alternative energy category excludes large hydropower projects that do not meet sustainability criteria (unless the project commits to meet IFC's performance standards) as those projects are likely to trigger negative externalities. And it excludes landfill or incineration without waste-to-energy components.

In 2018, the most common grounds for exclusion from the Index related to bonds' use of proceeds. For example, a green bond by Beijing Capital Polaris was excluded because the proceeds will be exclusively used for refinancing the acquisition of a waste management company in New Zealand, which has a large component of landfilling.

The index is widely used by green bond funds. In November, BlackRock announced the launch of its iShares Global Green Bond ETF, which tracks a dollar-hedged version of the index. And in 2018, UniCredit launched a green bond ETF that tracks the index.