[MilStdJunkie]

You've got to take into account that this is 15th C, after the first big wave of bubonic plague, which sent labor prices from "basically free" to "greater than the GDP of the entire continent". Whole new worlds of financial innovation were needed in this period, and not everyone was buying it. I suspect that this tax record itself was a relatively new project at the time, undertaken in part to control spiraling costs in a world without labor.