Fine by me. I'll concede that only the actual enumeration of the census be accepted if you will, too. That means the 1860 census results showing 30.8% of white households in the seceding states were also slaveholding households is correct, right?
You have provided no academically acceptable evidence that the 1860 census shows 30.8% of white households in the seceding states were also slaveholding households.
Simply saying it over and over is not a provision of evidence.
Take for example, actual words of DeBow, "Assuming the published returns, however, to be correct, it will appear that one-half of the population of South Carolina, Mississippi, and Louisiana, excluding the cites, are slaveholders...."
If you assume published returns to be correct, and if you exclude cities, you manufacture a desired statistic.
However, this is hardly an academically-accepted methodology.