More than 1,900 volunteers have assisted by reading deeds and recording the information we need to plot these covenants. We use optical character recognition (OCR) to identify property records containing racial language, but computers make mistakes. Volunteers have helped by confirming restrictive documents and recording information including the exact restriction wording, date of the deed or other document, seller and buyer, and the location of the property. That data allows us to map properties that were restricted.