The Consumer Sentinel Network (CSN) data book for January to December 2016 reports over 3 million complaints, with 42% being fraud-related, 13% identity theft, and 45% other complaints. Debt collection was the leading complaint category, followed by impostor scams and identity theft. The data, which is used exclusively by law enforcement, includes information from various state and federal agencies and shows trends in consumer complaints, especially regarding fraud and identity theft.