"Nielsen unveiled its first findings on viewership of TV shows on streaming services on Wednesday, providing data about select programs to media partners at a conference in Las Vegas, according to a presentation by the measurement specialist that was reviewed by The Wall Street Journal." Media companies have clamored for information about how TV shows perform on subscription video services like Netflix, Amazon, and Hulu, which don’t release ratings. "The new data from Nielsen are being shared privately with studios—except for whatever they agree to release more widely. They include metrics such as the total audience for episodes, the breakdown by age groups, and indications of whether streaming viewers are more likely to follow a show on traditional TV. ...Nielsen is only tracking streaming data for TV studios that 'opt in,' meaning those that ask for information on any shows or individual episodes for particular time frames. Studios provide audio files of their programs and Nielsen employs audio fingerprinting technology in its panel of 40,000 U.S. homes to measure viewing."