Out of 100 million you had 4,000 deaths?
Out of 100 million unvaccinated in the same age group, how many deaths were there?
we normally have just under 3 million deaths a year in the US in a population of about 330 million, call it one percent or so. So, out of 100 million we'd expect to have 100,000 deaths divided by 4, or 250,000, due to all causes.
You have to compare versus a control group.
(And yes, the 100 million or so vaccinated were not all vaccinated on Jan 1 of course, so it's spread out.)