70% of U.S. adults now vaccinated with at least one dose

70% of adults in the U.S. have gotten at least one dose of the COVID-19 vaccine as of Monday, according to the White House COVID-19 data director.

Source: 70% of U.S. adults now vaccinated with at least one dose - Axios

I want to know more about why this is happening despite general availability of vaccines. For example, is fear of Delta enough to have driven more vaccines?

Also note that this is adults, not the general population, so the minimum herd immunity number hasn’t been reached yet.

Still, this is encouraging.