All proposals require selection of the NSF Code from the drop down list, even if NSF is not the sponsor of the proposal. MIT uses these codes to report statistics in the annual Higher Education Research and Development (HERD) survey. One should select the general area of research from the drop down list, or ask the PI of the proposal for the appropriate category.
If this code is missing in proposal(s), RAS will reach out to the DAF to update this information at the end of each fiscal year.