In 2018 alone, wrongly convicted prisoners lost more than 1,600 years of life behind bars.

That's a new record, according to the annual report from The National Registry of Exonerations, which tracks all exonerations from 1989 onward. In 2018, 151 people were freed from serving sentences for crimes they did not commit. They had served 1,639 years altogether, an average of about 11 years per person.

Another record set last year is also worth our attention: More of these exonerations are happening in cases where misconduct by officials played a role. The report documents official misconduct in at least 107 exonerations last year. Official misconduct played a role in 80 percent of the 54 homicide cases in 2018 in which the person convicted was subsequently exonerated.

One of the big drivers of misconduct-fueled exonerations in 2018 was good old, corrupt Chicago. In 2017, Chicago saw its first-ever "mass exoneration" due to a corruption scandal involving Sgt. Ronald Watts. Watts was charged with leading his unit of officers in a massive protection racket where officers planted drugs on people who refused to pay extortion demands. In 2017, the convictions of 15 men were tossed out by prosecutors.

Further investigation into the extent of Watts' actions and those of his officers led to more exonerations in 2018. Another 31 defendants had their charges tossed out last year. And the report notes that even more exonerations have come this year—another 14 of them. The Watts cases have prompted the National Registry of Exonerations to rethink how it handles "group exonerations." Historically, this report has not included group exonerations in its statistics (the Watts exonerations from 2017 were not in its last report) because its definition calls for individualized re-examination of specific cases. After taking a closer look at the Watts cases, they've realized that even though these are group exonerations, the defendants are also seeing individualized reinvestigations. So they're going to start adding these exonerations to their statistics if they qualify.

Because of Chicago's police corruption, Illinois topped the list of states for exonerations last year, with 49. New York and Texas tied for second with 16 exonerations each, which shows just how much the behavior by Watts' crew shaped the overall statistics.

A few additional details from the latest report:

In 70 exonerations in 2018, the underlying crime never even happened. The Watts cases obviously fell into this category, but also worth noticing is that Vicente Benavides was freed from death row last April. He had been convicted 25 years ago for the rape, sodomy, and murder of a 21-month-old girl. The conviction was vacated after experts determined that the sexual assault did not happen and the injuries that killed the girl may have been the result of getting hit by a car.

In 19 exonerations, the defendant falsely confessed to the crime. All but two of these were murder confessions. Seven of these cases were in Cook County, Illinois, home of Chicago, but didn't involve Watts. Instead, it was a completely different corrupt cop, Det. Reynaldo Guevara, whose misconduct in wringing false confessions out of defendants has let to 14 exonerations so far.

Not only did 2018 set a record for the amount of time served by those who were exonerated, it saw another milestone: The number of years served by incarcerated people who were subsequently exonerated surpassed 20,000. That works out to an average of almost nine years served in jail for each person who has been exonerated.

Fewer than half of people who have been exonerated received any sort of compensation from the state for the years of their life that they've lost. States and local governments that have provided compensation have paid out more than $2.2 billion to exonerated prisoners. The report is quick to remind us that this does not include the costs to taxpayers of having prosecuted and incarcerated these people in the first place.

Two of the longest-serving defendants in the history of the registry were exonerated in 2018. Richard Phillips served 45 years in Michigan for a murder conviction from 1972. Wilbert Jones served 44 years for a sexual assault conviction in Louisiana. Both were convicted due to sketchy testimony.

Check out the full report here. The National Registry of Exonerations is put together by the University of California Irvine Newkirk Center for Science and Society, the University of Michigan Law School, and the Michigan State University College of Law.