Distribution of wealth at the end of the Viking Age

How concentrated was wealth at the end of the Viking Age?
In lecture 34 of his course The Vikings, from The Great Courses Prof Kenneth Harl tries to frame up the dispersal of wealth in Scandinavia at the end of the Viking Age.
He makes the following estimates of the concentration of land ownership in the late 12th and earliest 13th century. This would reflect the increased trade and improved agriculture that occurred as Norway, Sweden, and Denmark fully embraced Christianity and had well-developed territorial monarchies.