Exactly. Without Noah, it’s a straight-line slope. Even with Noah, there’s no precipitous drop if the x axis plots time (my first chart last post) instead of generations, since Noah was 500 when he had his sons.
It’s worth noting that Noah’s numbers aren’t given in the Genesis 11 genealogy that shows the post-flood decline. His total age is much higher than his father and higher than everyone in the first half of Adam’s genealogy in Genesis 5. He had the third-highest lifespan in the Bible, so of course a chart that starts with him will show a big drop.
Further, if this decay curve is supposed to arise due to environmental conditions changed by the flood, keep in mind that Noah lived 600 years before the flood (even Shem lived 100 years before the flood). I don’t know how one wants to suppose a flood affects 600- and 100-year-old people’s lifespans, but if we assume those pre-flood centuries gave them some kind of a bump in total years lived, any hint of a sharp decline at the beginning of the chart evaporates.
But maybe I’m wrong. Maybe I’m just trying to explain away the obvious. If so, I have exciting news: the New Testament also has a decay curve hidden within it. This one is even clearer. It’s found in the length of Paul’s writings to the church. This begins with Acts, of course, which includes material about Paul by his associate, Luke. Then is Romans, 1 Corinthians, etc. to Philemon. Here it is in all its glory, easily found by counting the verses in each book and plotting them in their canonical order:
Some naysayers may object to my inclusion of Acts, but Acts fits as clearly as Noah fits into a plot of post-flood lifespans. They may suggest that if I include Acts I should include Luke too, but this ignores the distinction Pentecost makes. Adding one of the gospels means we’re not plotting the same thing anymore. That would be like adding Lamech before Noah, ignoring the distinction the flood makes.
No, obviously the decay curve is real. It beggars belief to think Paul contrived this pattern through carefully shortening the length of his letters. Those who ordered our New Testament wouldn’t have had the mathematical acumen to create it. A pattern like this could not have been imposed from below, so it must come from above. 