Some documents have several dates on them. Vital records will contain the date of the event, Deeds will contain the date the deed was executed. Wills include the date the will was signed. Some documents contain the date the document was recorded. Wills should contain the date the will was admitted to probate. Deeds may include the date the deed was acknowledged. Each of these dates are a clue in the chronology of the document. Always determine the reason for any date listed on a document–all of them.
In the 19th century, some of the United States census enumeration included more than population schedules. There were also agricultural, industrial and other schedules. Have you looked at these non-population schedules for information about your ancestor?