Ditto to KB's comments, in the absence of a more organized process, you can have a nonprofit provide you with the demographics of the clients they serve as evidence that they are seving primarily low-and-moderate income individuals. Many health and human service organizations will have annual reports to their funders already prepared that should meet your needs to evidence CRA credit.
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Societies that do not find work in and of itself "pleasing to God and requisite to Man," tend to be highly corrupt.