In about 1600, Bishop James Usher, a prolific scholar and church leader in Ireland, using this method, calculated that Adam was born in the year 4004 BC.
The Bible provides the entire genealogical record starting with Adam and ending with Joseph and Mary. Beginning with David, as shown in the chart above, the Bible gives the family tree of both Joseph and Mary.
The genealogies are in Genesis 5, Matthew 1, and Luke 3, plus segments in other books of the Bible. Virtually all Bible scholars agree that there are no gaps in these reported famly lines.
Over the last 400 years, many other people have drawn the family tree from their own study of the Bible, by hand and by computer analysis, and nearly everyone comes to the same conclusion: Adam was born about 4000 BC.