To give a description of the problem in text...
Both charts are labeled "Deaths", but I'm going to describe one of them for you.
The time span from 1981 to 1999 goes like this: 1,968,365 - 1,998,559 - 2,033,124 - 2,068,679 - 2,091,359 - 2,105,024 - 2,163,984 - 2,161,764 - [1,637,394] - [2,656,721] - 2,180,115 - 2,226,027 - 2,282,854 - 2,284,363 - 2,317,918 - 2,321,933 - 2,330,759 - 2,359,088 - 2,386,995
And then 2000 is [2,979,442]
And then 2001 is 2,430,225
And so on. Every 10 years, and also in 1989, there is a fluctuation by 500,000 deaths from the expected number given the surrounding trends.
All of the numbers that are _not_ between [] above look like a smooth upward trend, yeah? So WTF is happening in the three that have [] if the data isn't bogus? I say the data must be bogus.
https://www.archives.gov/publications/prologue/1996/spring/1...
I can't look at your link at the moment because the corporate firewall is currently blocking the domain.
But there really isn't any way to get around the fact that real census data are only collected once every 10 years (and the 1890 census was burned, so that point is missing).