Facebook could be a literal ghost town in a few decades' time, with the dead outnumbering the living.
Experts at Oxford University crunched the numbers, and found based on the social media giant's present userbase, at least 1.4 billion of its members will die by the year 2100.
But if its rapid expansion over the last decade continues, there could be 4.9 billion pages belonging to the dead by then.
Either way, by 2070 it's expected there will be more pages belonging to dead people than living.
"These statistics give rise to new and difficult questions around who has the right to all this data, how should it be managed in the best interests of the families and friends of the deceased and its use by future historians to understand the past," said Carl Öhman of the Oxford Internet Institute.
"Never before in history has such a vast archive of human behaviour and culture been assembled in one place," said his colleague David Watson, who contributed to the study.
"Controlling this archive will, in a sense, be to control our history. It is therefore important that we ensure that access to these historical data is not limited to a single for-profit firm. It is also important to make sure that future generations can use our digital heritage to understand their history."
- Journalist's eerie story adds fuel to claims Facebook is listening to us
- New Zealand's most Facebook-savvy MPs revealed
There are presently about 2.3 billion people using Facebook every month, making it easily the most popular social network in the world. It grew 9 percent in 2018, despite a string of scandals.
Assuming Facebook doesn't grow beyond its current userbase, nearly half the dead will be from Asia, mostly India and Indonesia. Under the growth scenario, most will be from Africa - Nigeria in particular. Western users will be a minority, with only the US making the top 10.
"Facebook should invite historians, archivists, archaeologists and ethicists to participate in the process of curating the vast volume of accumulated data that we leave behind as we pass away," said Watson.
"This is not just about finding solutions that will be sustainable for the next couple of years, but possibly for many decades ahead."
Their study was published in journal Big Data & Society.