I think Vitas pretty much says it all really.
That stuffed reversed population growth back 1/2 a century or more, IIRC.
a little more then that..
Remember, VITAS was treatable. Very expensive to treat with very rare drugs, but treatable.
So who got saved? The rich. Who has a low birth rate? The rich.
Who died off in droves? The poor. To the point that some countries (like Morocco?) were almost completely depopulated. However, the poor also have high birth rates.
So what you end up with is wealthy countries having the least deaths, and those deaths confined to the poorest class. While in poor countries, you have massive death with only a few surviving.
During the VITAS outbreaks, cities either saved or killed you, depending on your countries supply of medicine. In wealthy countries, being in a city meant quick emergency response. However in poor countries that didn't have treatments, cities became killing grounds as you now jammed so many hosts for the virus to pass to in a geographically small area.
And don't forget to use the numbers from 1985. (SP was published in 1988/89 or so, and the numbers just continue from there).
No, I think the bigger killers in Seattle and North America where the Nights of Rage. No one REALLY knows how many meta humans died in those nights of fire.... And my guess is its a lot higher then the 'official' numbers.
Or, a 3rd possibility.
The info we are using itself is a '3rd wall' document. Meaning we, as players, are seeing a document from inside the fiction, and not a document ABOUT the fiction.
(something they do like to do....)
And, who compiles those stats in game? What advantages do they have for putting a spin on it? Where are they getting their info? What are their accuracy rating?