The only count starting around year 0 is the count of twelve years, the count of Chesed. This count combines with the count of nineteen years since the Arizal, and with the Yovel count starting at 5727, as we have seen. Together, these counts reach value 507 in year 5776, and that will be the end of these counts together. The year 5776 is 77 times 75 years after year 1. So, we do agree. The cut-off of the count of Chesed, at 77 times 75, is correct. There is a cycle of 75 years.
וְלֶמֶךְ, שִׁבְעִים וְשִׁבְעָה