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Today, because there were just two of us, we continued work on DER-105. We added the notion of a basket of commodities, which was missing from the commodities ontology, and loosened the constraints on the definition of a reference index with respect to the kinds of baskets that could comprise the index to allow for any weighted basket, including potentially any commodity-specific basket.
See also https://www.spglobal.com/spdji/en/documents/methodologies/methodology-dj-commodity-index.pdf for a discussion of how such baskets are put together.