Half of the US’s top 100 companies are now reporting on their environmental, social and governance (ESG) performance, according to a study by social investment researchers.

Of the companies in the S&P 100 Index, 49 had issued comprehensive ESG reports – 11 for the first time – in the period from June 2005 to December 2006, said the Social Investment Research Analysts Network (SIRAN) and KLD Research & Analytics, a Boston, Massachusetts–based investment research firm.

More than one-third (38) of the companies have adopted the guidelines laid down by the Global Reporting Initiative (GRI), the study, now in its third year, found.

"We’ve essentially reached a tipping point where nearly half of these leadership companies are reporting on their ESG performance. In a few years, this kind of reporting will be standard business practice, and companies that do not issue reports will become the exception, rather than the rule," said Steve Lippman, vice president of asset research at Boston, Massachusetts-based Trillium Asset Management.

The 11 companies issuing comprehensive reports for the first time included Bank of America, Caterpillar, Cisco, Heinz, Merck and Xerox.

The last study found 43 firms issued ESG reports and 34 used the GRI guidelines.

However, this upward trend may have been influenced by the fact that this year’s study covered an 18-month period, whereas the previous reports covered 12 months, and by the update of the GRI guidelines in October 2006, said KLD research project manager Katy Chapdelaine.

The number of companies reporting ESG content on their websites was 79 – a figure unchanged from the previous study.