The phrase "ever since the existence" is correct and usable in written English.
It is used to describe something that has been true for a long period of time. For example, "The company has been a leader in its industry ever since the existence of the business."
as code for "Jew" or "Israeli" "Zionism" denotes a movement, forged in the late 19th century and evolving ever since, for the existence of a modern Jewish state in the land of Israel.
Zero Dark Thirty, from director Kathryn Bigelow and screenwriter Mark Boal, has been at the centre of controversy in the US ever since its existence was revealed in the wake of Bin Laden's killing at his compound in northern Pakistan in May last year by a US Navy Seal squad.
Originally released by United Artists or RKO, they've been leading a nomadic existence ever since, as rights have passed from one company to another.
That reminds me, you said something to me 8 months ago that really hurt my feelings and I've secretly resented your existence ever since!" Classic denial really.
We have had war on the subject of slavery ever since our existence as a nation".
It shows that piracy came into existence ever since the artistic dawn, however digital piracy is much younger.
This property of the centrifuge has plagued policymakers ever since the centrifuge machine came into existence.
The elite classes have been imagining nations into existence ever since the marriage of capitalism to the printing press, he believed, and the communication of identity mattered just as much as the conception of it.
Samsung's ATIV Odyssey has been a real noodle-scratcher of a device ever since its existence was first hinted at during Microsoft's Windows Phone 8 launch event.
Harper Lee's "Go Set a Watchman" is undoubtedly one of the most anticipated books in recent literary history, and its contents have been closely guarded ever since its existence was announced in February.
