It would seem quite obvious where X and Y would originate.
You seem to have missed the point of a couple of previous posts.
No one is arguing with the origin point. The numbers were cooked to come up with that value.
The curves given predict a starting point for this population curve and predict the current population today. They were set up to do so.
However, the point is that they also predict a bunch of intermediate population figures. You have been given some.
And your comment on those intermediate figures is...?
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