Green-ealogy is the cemetery's research service. With more than 560,000 burials, the earliest dating to 1840, Green-Wood estimates that its genealogical information relates to over 20 million individuals alive today. That translates to a massive volume of unique genealogical resources. There is often variation within the individual records, but most of Green-Woods files contain vital information for each burial: the cause of death, age at death, and late residence. Many also have the names of other family members, original family and business correspondence, and other unique documents.