The Green Century Balanced Fund has released an analysis of the greenhouse emissions of the companies it holds in its portfolio that shows the fund's "carbon intensity" is 66% less than that of the Standard & Poor's 500 Index.

The fund announced the results today of the carbon footprint analysis done by Trucost, a leading environmental data firm, and is believed to be the first U.S. mutual fund to release such a report. A carbon footprint is determined by measuring greenhouse gas emissions, a leading cause of climate change, and converting them into carbon equivalents.

Trucost measured the tons of carbon emissions per million dollars of revenue of the companies held by the Green Century fund and those that are part of the S&P 500 to arrive at the results.

Green Century Balanced Fund's low carbon intensity is mainly attributable to the fund's underweighting or avoidance of the utilities, oil and gas, and basic resources sectors. Being free of fossil-fuel production or manufacturing companies contributed to the relative positive environmental impact of the fund.

In April, Trucost did a similar analysis on 91 mutual funds and issued a report, Carbon Counts USA. That report evaluated the 91 mutual funds (including 16 socially responsible or sustainability funds) based on the greenhouse gas emissions of the companies in their portfolios. Although the report named all of the funds it evaluated, Trucost did not release a complete ranking. But it did name the five funds with the lowest carbon footprint and the five with the highest. The five funds with the lowest carbon footprint included only one SRI fund, Ariel Appreciation Fund.

Green Century Balanced Fund was not part of that analysis, but its carbon footprint-126 tons of carbon per million dollars of revenue of each of the fund's portfolio holdings-is almost half the average footprint of the 16 sustainability and socially responsible investing funds (226 tons of carbon per million dollar of revenue of each of those funds' portfolio holdings) analyzed in the Carbon Counts report.

In the report, the fund with the lowest carbon footprint was Financial Select Sector SPDR fund at 40. The one with the highest was iShares FTSE/Xinhua China 25 Index Fund at 1,549. The S&P 500's footprint was 384.

Erin W. Gray, Green Century's director of marketing and strategic analysis, said Green Century Balanced Fund was not part of the Carbon Counts report because Trucost focused primarily on all-equity portfolios and its balanced fund includes bonds.

"We saw the April report that Trucost created and thought it'd be great to see how our balanced fund performed in terms of carbon intensity because it has a specific green and environmental focus. We are excited about the results, but think it is just as important that we are publicly releasing this data," Gray said. "With this report, we believe we are taking an important step toward more comprehensive carbon accounting. This move sets a new standard for transparency and disclosure of environmental data within the mutual fund industry. We also hope it encourages companies to continue to increase their carbon disclosures and lets them know that investors find this information critical."

The methodology of Trucost's carbon audit included calculating the direct and indirect (major supplier) greenhouse gas emissions for each company in the Green Century Balanced Fund portfolio as of April 30, 2009. Each holding's contribution to the emissions profile of the portfolio is then calculated on an equity ownership basis. The carbon footprint of the Green Century fund is normalized by its value to produce a measure of carbon intensity.

The Green Century Balanced Fund's returns for the one-, three-, five-, and ten-year periods ended June 30, 2009, were -13.36%, -3.78%, -1.05%, and 4.64%, respectively. The S&P 500 returns for the one-, three-, five- and ten-year periods ended June 30, 2009, were -26.21%, -8.22%, -2.24% and -2.22%, respectively.