It’s official: In 2016, more Americans died of drug overdoses than any other year on record — the latest harrowing development in America’s opioid epidemic.

The latest figures come from a new report by the Centers for Disease Control and Prevention (CDC). The agency has been releasing preliminary figures for overdose deaths throughout the year, but this new report provides a final, official count for 2016.

Last year, more than 63,600 people died of drug overdoses, up from more than 52,400 in 2015. About two-thirds of overdose deaths — more than 42,200 — were linked to opioids. (That may be an underestimate; one study found that opioid overdose deaths, although not overall overdose deaths, are likely undercounted.) And for the first time, the deadliest opioid was not conventional painkillers or heroin — but non-methadone synthetic opioids like fentanyl, which were linked to more than 19,400 overdose deaths in 2016.

In comparison, more than 58,000 US soldiers died in the entire Vietnam War, nearly 55,000 Americans died of car crashes at the peak of such deaths in 1972, more than 43,000 died due to HIV/AIDS during that epidemic's peak in 1995, and nearly 40,000 died of guns during the peak of firearm deaths in 1993. Drug overdoses in 2016 killed more people than any of those.

Another CDC report released on Thursday found that life expectancy in the US dropped for the second year in a row — by 0.1 years to 78.6 — in part due to a rise in unintentional injuries, such as overdoses.

The CDC’s preliminary data for 2017 only goes through May. But based on the very early numbers, it looks like 2017 may be even worse.

The numbers show the evolution of the opioid epidemic.

The opioid crisis began in the 1990s, when doctors became increasingly aware of the burdens of chronic pain. Pharmaceutical companies saw an opportunity, and pushed doctors — with misleading marketing about the safety and efficacy of the drugs — to prescribe opioids to treat all sorts of pain.

Doctors, many exhausted by dealing with difficult-to-treat pain patients, complied — in some states, writing enough prescriptions to fill a bottle of pills for each resident. The drugs proliferated, landing in the hands of not just patients but also teens rummaging through their parents’ medicine cabinets, other family members, friends of patients, and the black market.

Eventually, some painkiller users moved on to other opioids, like heroin or fentanyl and its analogs. Not all painkiller users went this way, and not all opioid users started with painkillers.

But statistics suggest many did: A 2014 study in JAMA Psychiatry found 75 percent of heroin users in treatment started with painkillers, and a 2015 analysis by the CDC found people who are addicted to painkillers are 40 times more likely to be addicted to heroin. (Although a more recent study found that while a majority of people in treatment for opioid use disorder in 2015 started with painkillers, an increasing amount started with heroin compared to the decade before.)

The issue has really turned into two simultaneous crises — which Keith Humphreys, a Stanford University drug policy expert, has described as the dual problems of “stock” and “flow.”

On one hand, you have the current group of opioid users who are addicted; the people in this population need treatment or they will simply find other, potentially deadlier opioids to use if they lose access to prescribed painkillers. On the other hand, you have to stop new generations of potential drug users from accessing and misusing opioids.

Addressing these crises will, experts say, require tens of billions of federal dollars. As I previously explained, we have a pretty good idea of what those resources should go to: They could be used to boost access to treatment (particularly the highly effective medication-assisted treatment), pull back lax access to opioid painkillers while keeping them accessible to patients who truly need them, and adopt harm reduction policies that mitigate the damage caused by opioids and other drugs.

Some states are attempting to seriously confront this crisis. Vermont, for example, has built a “hub and spoke” system that treats addiction as a public health issue and integrates treatment into the rest of health care. Possibly as a result, Vermont had the lowest overdose death rate in 2016 out of any state in New England. (For more on Vermont, check out my in-depth breakdown of the state’s system.)

Addressing all of this, however, will take an acknowledgment of the crisis and serious resources to do something about it. Despite some funding here and there, the level of commitment that experts say is required has not come from the federal government — and so the crisis keeps getting worse and worse.

For more on the opioid epidemic, read Vox’s explainer.