The Centers for Disease Control and Prevention have allocated just 700,000 doses of the shot for the week of April 12. That’s down considerably from this week’s 4.95 million doses and last week’s 1.9 million doses.

The CDC chart does not offer a reason for the precipitous drop, but J&J has encountered issues with manufacturing the drug. An error at one contractor’s plant affected 15 million doses worth of a key ingredient in the J&J vaccine. The company has since taken over control of that plant.

Regardless of the reason, the shortage could slow down vaccination efforts by the government. J&J’s single-dose vaccine has been seen as a key solution to reaching people in rural areas and those who could be harder to track for a follow-up dose, such as college students, as the school year nears its end. The decrease also comes as more states lower their thresholds for vaccine eligibility to age 16. President Biden has called for all adults to be eligible by April 19.

The number of Moderna and Pfizer vaccines will go up slightly next week, but are largely the same as this week.

It’s a big drop for states. Washington, for instance, will get 12,900 doses next week, compared with over 100,000 this week. California, Texas, and Florida will get the biggest shipments of the J&J vaccine next week. Some outlying U.S. islands, like Micronesia and Guam, will get none. Wyoming is at the bottom of the state list, in line to receive just 1,000 doses.

J&J, based in New Brunswick, N.J., said last week that it had beat its March delivery target, providing the U.S. government more than 20 million doses, and that it expects to deliver another 24 million by the end of April. Biden has set a goal for almost 100 million J&J doses by the end of May.