The U.S. distributed the 100 millionth dose of the coronavirus vaccine on Friday, the White House COVID-19 response team confirmed.

Why it matters: The achievement puts the Biden administration well ahead of schedule for its goal of distributing 100 million doses in the first 100 days in office, and emphasizes the extent to which the administration has aggressively ramped up vaccination efforts.

Details: In a speech at the White House Thursday, President Biden noted that the U.S. is now distributing an average of 2.5 million shots per day, far ahead of most countries.

• "Eight weeks ago, only 8% of seniors — those most vulnerable to COVID-19 — had received a vaccination. Today, 65% of people age 65 or older have received at least one shot, and 36% are fully vaccinated."
• "That's key, because this is a population that represents 80% of the well over 500,000 COVID-19 deaths that have occurred in America."
• "We have nearly doubled the amount of vaccine doses that we distribute to states, tribes and territories each week."
• "These milestones are significant accomplishments, but we have much more to do, much more to do. The American rescue plan will help us do it."

What's more: Biden emphasized the threat posed by emerging variants and urged Americans to stay vigilant against the virus.

• "Wash your hands and stay socially distanced, and keep masking up as recommended by the CDC, and get vaccinated when it's your turn. Now is not the time to let down our guard."
• "In the last week we've seen increases in the number of cases in several states. Scientists have made clear that things may get worse as new variants of the virus spread. Getting vaccinated is the best thing we can do to fight back against these variants. "

The big picture: Given the 7-day average of new reported doses, the U.S. is currently on pace to have roughly 50% of the population vaccinated by May.

• "If we keep our guard up, stick together and stick with the science, we can look forward to a 4th of July that feels a bit more normal," Biden said Thursday.

But, but, but: While opening up eligibility could get more shots in arms, Axios' Caitlin Owens wrote earlier this week, it also risks creating more competition for vaccines before many vulnerable Americans have received theirs.

What's next: Biden noted in his speech that the White House will announce its next "shots in arms" goal next week.

• "We may be able to double it," Biden told reporters on his way to Atlanta on Friday, indicating that the next goal could be to reach 200 million doses by his 100th day in office, AP reported.