Drug makers and medical device makers are still spending between $2.1 billion and $2.2 billion a year to woo doctors into prescribing and using their products, according to a new investigation by ProPublica.

Between 2014 and 2018, more than 600,000 of the approximately 1.1 million doctors in the US received at least one payment from industry in any given year. The payments were for things including speaking fees, consulting, meals, gifts, travel, and royalties.

While thousands of doctors have made $100,000 or more, more than 2,500 received $500,000 or more in the five-year period—and those payments do not include royalties. More than 700 received at least $1 million.

The data comes from the first full five-year period of the federal Open Payments Initiative, a part of the 2010 Affordable Care Act that requires companies to disclose such payments. The idea behind the initiative was that such transparency might dissuade industry payments to physicians, which research has shown time and again influences prescribing and care practices.

But researchers and industry watchers see little change in spending levels and the number of physicians accepting payments.

“It makes me wonder whether patients are using this information or whether physicians are even aware this information is out there,” Dr. Joseph Ross, a professor of medicine and public health at Yale who has studied pharmaceutical marketing, told ProPublica. “It’s almost like it’s not happening.”

In an email to ProPublica, a spokesperson for the industry trade group Pharmaceutical Research and Manufacturers of America (PhRMA) defended the continued practice, writing:

It is not necessarily a negative that the numbers have remained generally flat over the past five years… That statistic appears to be consistent with companies’ belief that their interactions with physicians have been and remain legitimate, even when subjected to sunshine.

The data also includes how much drug makers have spent to promote specific drugs to physicians over the five years. In 2018, drug makers shelled out $17.9 million to promote blood thinner Xarelto to doctors, $12.6 million to promote diabetes drug Farxiga, and $12.2 million to promote the immune-suppressive drug Humira. Those figures do not include money for research funding or royalties.

A 2017 analysis on the drugs that prompted the most physician-promotion payments from doctors found that they tended to be drugs that are “less likely than top selling and top prescribed drugs to be effective, safe, affordable, novel, and represent a genuine advance in treating a disease.”