NEW YORK, July 16 (Reuters) - Goldman Sachs Group Inc trimmed its commodities trading risk in the second quarter as raw materials prices declined, quarterly results from the Wall Street investment bank showed on Tuesday. Goldman's Value-at-Risk in commodities stood at $19 million per day in the second quarter, down $2 million from the first quarter and $1 million lower than a year earlier. VaR is a measure of the maximum amount of money a bank is prepared to lose in a day from trading a particular asset class. Like other Wall Street banks, Goldman groups its commodities revenue under the fixed income category and does not break out the sector individually. As a result, VaR is often one of its key risk-reward indicators for commodities. JPMorgan Chase & Co, a rival of Goldman, also reported a slight decline in its second-quarter commodities risk as oil, metals and crop prices fell in the period. The Thomson Reuters-Jefferies CRB index, a key indicator of commodity prices, declined 7 percent in the second quarter. Goldman Sachs said second-quarter fixed income revenue rose 12 percent from a year earlier to $2.46 billion, helped by significantly higher net revenue in currencies, credit products and commodities. The bank's quarterly profit doubled to $1.86 billion from $927 million a year ago as it made more money trading bonds before an interest-rate spike hit markets in June. Wall Street banks' average commodities VaR by quarter (millions of dollars per day): Q2 Q1 Q4 Q3 Q2 Q1 Q4 Q3 Q2 2013 2012 2011 * JPMorgan 13 15 14 13 13 21 20 15 16 * Goldman Sachs 19 21 20 22 20 26 26 25 39 * Morgan Stanley n/a 20 22 22 34 27 28 32 29 * Bank of America n/a 13 15 12.5 11.9 13.1 12.1 15.7 23.7 ** Citigroup n/a 34 13 15 18 14 18 21 25 * Value-at-Risk based on a 95 percent confidence level ** Value-at-Risk based on a 99 percent confidence level Notes: Morgan Stanley is to report its Q2 earnings and commodities risk on July 18. Bank of America and Citigroup are to report VaR data separately in later 10-Q filings with the Securities & Exchange Commission.