It is one of the most common complaints levelled at firm's sustainability reports: they are difficult to navigate and hard to compare.

Now leading standards body the Global Reporting Initiative (GRI) has launched a new taxonomy modelled on the tagging standards already used for financial reports that promises to make it much easier for investors and stakeholders to assess corporate sustainability reports, according to sister publication .

Unveiled last week, the new taxonomy has been developed in collaboration with consultancy Deloitte Netherlands and has been made freely available to sustainability professionals around the world.

It builds on the existing eXtensible Business Reporting Language (XBRL) that firms commonly use to tag data in their financial reports, making it easier for interested parties to search for data and compare it with other firms.

The GRI taxonomy extends the model to apply to common environmental and social data found in sustainability reports, such as carbon emissions, water use and human rights infringements.

"Today's new taxonomy is a major step forward in making sustainability data available to society," said Nelmara Arbex, deputy chief executive of the GRI in a statement. "Many companies already use XBRL to tag their financial performance data; the GRI Taxonomy means that companies can tag their sustainability data, making it easily accessible for people who want to find information in the report."

The news came in the same week as the GRI released the results of the first public comment period for the next iteration of its reporting guidelines, dubbed G4.

The consultation attracted more than 1,800 submissions, with the majority indicating they want to see GRI more clearly define topics and indicators that should be included in sustainability reports and provide more guidance on how to develop integrated financial and non-financial reports.

The exercise also resulted in calls for the GRI to introduce new guidance or update reporting guidance on business ethics, greenhouse gas emissions, eco-innovation, life cycle assessment, water and biodiversity.