Robocalls made up nearly three-quarters of complaints from consumers about violations of the National Do Not Call Registry over the past year, the Federal Trade Commission announced Thursday. Calls from impostors jumped from the third-most complained-about topic in 2018 to No. 1 this year.

The FTC on Thursday released its 2019 Do Not Call Registry Data Book, a listing of the most common complaints across the U.S. and in individual states from consumers who say they received calls despite being on the registry.

More than 239 million people were actively signed up to the Do Not Call Registry from October 2018 to September 2019, but the FTC still received more than 5.4 million complaints about violations. That's down from 5.8 million in the 2018 report, but the FTC says the numbers are skewed because of the 35-day government shutdown at the start of the year.

Seventy-one percent of those complaints were about robocalls while the other 21% were calls from a live person.

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Top complaints by topic of calls

  1. Impostors (574,501 complaints)
  2. Medical and prescriptions
  3. Reducing debt
  4. Computer and tech support
  5. Warranty and protection plans
  6. Vacation and timeshares
  7. Energy, solar and utilities
  8. Money making opportunities
  9. Home improvement and cleaning
  10. Lotteries, prizes and sweepstakes
  11. Home security and alarms

October 2018 saw the most grievances (587,776) and most months had at least 400,000. There was a noticeable drop in December 2018 (379,360) and January 2019 (130,674), again due to the government shutdown.

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The state with the most gripes overall was California with 652,024 -- not a surprise given its population. The state with the most complaints compared to its population was Colorado. There were 2,294 complaints for every 100,000 residents. 

Top 10 states for complaints

(per 100,000 people)

  1. Colorado
  2. Oregon
  3. Arizona
  4. New Jersey
  5. Nevada
  6. Maryland
  7. Delaware
  8. Virginia
  9. Connecticut
  10. New Hampshire

The state with the fewest complaints per 100,000 people was Alaska (581).

States with the most people signed up to the Do Not Call Registry (per 100,000 people)

  1. New Hampshire (93,339)
  2. Connecticut
  3. Massachusetts
  4. Maine
  5. New Jersey
  6. Kansas
  7. Vermont
  8. Wyoming
  9. Wisconsin
  10. Pennsylvania

California had the most people registered overall with more than 26 million but ranked 40th in registrations per 100,000 people.