Question: How many iPods did its manufacturers reveal was sold in April 2007?

full_context: Document 1: Macintosh: In recent years, Apple has seen a significant boost in sales of Macs. This has been attributed, in part, to the success of the iPod and the iPhone, a halo effect whereby satisfied iPod or iPhone owners purchase more Apple products, and Apple has since capitalized on that with the iCloud cloud service that allows users to seamlessly sync data between these devices and Macs. Nonetheless, like other personal computer manufacturers, the Macintosh lines have been hurt by consumer trend towards smartphones and tablet computers (particularly Apple's own iPhone and iPad, respectively) as the computing devices of choice among consumers.
Document 2: IPod: Since October 2004, the iPod line has dominated digital music player sales in the United States, with over 90% of the market for hard drive-based players and over 70% of the market for all types of players. During the year from January 2004 to January 2005, the high rate of sales caused its U.S. market share to increase from 31% to 65% and in July 2005, this market share was measured at 74%. In January 2007 the iPod market share reached 72.7% according to Bloomberg Online.
Document 3: IPod Shuffle: The iPod Shuffle (stylized and marketed as iPod shuffle) is a digital audio player designed and marketed by Apple Inc. It was the smallest model in Apple's iPod family, and was the first iPod to use flash memory. The first model was announced at the Macworld Conference & Expo on January 11, 2005; the fourth - and final - generation models were introduced on September 1, 2010. The iPod Shuffle was discontinued by Apple on July 27, 2017.
Document 4: IPod: Though the iPod was released in 2001, its price and Mac-only compatibility caused sales to be relatively slow until 2004. The iPod line came from Apple's "digital hub" category, when the company began creating software for the growing market of personal digital devices. Digital cameras, camcorders and organizers had well-established mainstream markets, but the company found existing digital music players "big and clunky or small and useless" with user interfaces that were "unbelievably awful," so Apple decided to develop its own. As ordered by CEO Steve Jobs, Apple's hardware engineering chief Jon Rubinstein assembled a team of engineers to design the iPod line, including hardware engineers Tony Fadell and Michael Dhuey, and design engineer Sir Jonathan Ive. Rubinstein had already discovered the Toshiba disk drive when meeting with an Apple supplier in Japan, and purchased the rights to it for Apple, and had also already worked out how the screen, battery, and other key elements would work. The aesthetic was inspired by the 1958 Braun T3 transistor radio designed by Dieter Rams, while the wheel based user interface was prompted by Bang & Olufsen's BeoCom 6000 telephone. The product ("the Walkman of the twenty-first century" ) was developed in less than one year and unveiled on October 23, 2001. Jobs announced it as a Mac-compatible product with a 5 GB hard drive that put "1,000 songs in your pocket."
Document 5: IPod: The iPod is a line of portable media players and multi-purpose pocket computers designed and marketed by Apple Inc. The first version was released on October 23, 2001, about ​ 8 ⁄ months after the Macintosh version of iTunes was released. As of July 27, 2017, only the iPod Touch remains in production.
Document 6: IPod Touch (6th generation): The sixth - generation iPod Touch (stylized and marketed as the iPod touch, and colloquially known as the iPod touch 6G, iPod touch 6, or iPod touch (2015)) is a multipurpose pocket computer designed and marketed by Apple Inc. with a touchscreen - based user interface. It is the successor to the iPod Touch (5th generation), becoming the first major update to the iPod lineup in more than two and a half years. It was released on the online Apple Store on July 15, 2015, along with a new iPod Nano and iPod Shuffle, which received minor upgrades.
Document 7: IPod: On October 22, 2007, Apple reported quarterly revenue of US$6.22 billion, of which 30.69% came from Apple notebook sales, 19.22% from desktop sales and 26% from iPod sales. Apple's 2007 year revenue increased to US$24.01 billion with US$3.5 billion in profits. Apple ended the fiscal year 2007 with US$15.4 billion in cash and no debt.
Document 8: IPod: Many accessories have been made for the iPod line. A large number are made by third party companies, although many, such as the iPod Hi-Fi, are made by Apple. Some accessories add extra features that other music players have, such as sound recorders, FM radio tuners, wired remote controls, and audio/visual cables for TV connections. Other accessories offer unique features like the Nike+iPod pedometer and the iPod Camera Connector. Other notable accessories include external speakers, wireless remote controls, protective case, screen films, and wireless earphones. Among the first accessory manufacturers were Griffin Technology, Belkin, JBL, Bose, Monster Cable, and SendStation.
Document 9: IPod: In mid-2015, several new color schemes for all of the current iPod models were spotted in the latest version of iTunes, 12.2. Belgian website Belgium iPhone originally found the images when plugging in an iPod for the first time, and subsequent leaked photos were found by Pierre Dandumont.
Document 10: IPod: The iPod is a line of portable media players and multi-purpose pocket computers designed and marketed by Apple Inc. The first line was released on October 23, 2001, about 8½ months after iTunes (Macintosh version) was released. The most recent iPod redesigns were announced on July 15, 2015. There are three current versions of the iPod: the ultra-compact iPod Shuffle, the compact iPod Nano and the touchscreen iPod Touch.
Document 11: IPod: On January 22, 2008, Apple reported the best quarter revenue and earnings in Apple's history so far. Apple posted record revenue of US$9.6 billion and record net quarterly profit of US$1.58 billion. 42% of Apple's revenue for the First fiscal quarter of 2008 came from iPod sales, followed by 21% from notebook sales and 16% from desktop sales.
Document 12: IPod: Before the release of iOS 5, the iPod branding was used for the media player included with the iPhone and iPad, a combination of the Music and Videos apps on the iPod Touch. As of iOS 5, separate apps named "Music" and "Videos" are standardized across all iOS-powered products. While the iPhone and iPad have essentially the same media player capabilities as the iPod line, they are generally treated as separate products. During the middle of 2010, iPhone sales overtook those of the iPod.
Document 13: IPod: On April 9, 2007, it was announced that Apple had sold its one-hundred millionth iPod, making it the biggest selling digital music player of all time. In April 2007, Apple reported second quarter revenue of US$5.2 billion, of which 32% was made from iPod sales. Apple and several industry analysts suggest that iPod users are likely to purchase other Apple products such as Mac computers.
Document 14: IPod: On October 21, 2008, Apple reported that only 14.21% of total revenue for fiscal quarter 4 of year 2008 came from iPods. At the September 9, 2009 keynote presentation at the Apple Event, Phil Schiller announced total cumulative sales of iPods exceeded 220 million. The continual decline of iPod sales since 2009 has not been a surprising trend for the Apple corporation, as Apple CFO Peter Oppenheimer explained in June 2009: "We expect our traditional MP3 players to decline over time as we cannibalize ourselves with the iPod Touch and the iPhone." Since 2009, the company's iPod sales have continually decreased every financial quarter and in 2013 a new model was not introduced onto the market.
Document 15: IPod: In mid-2015, a new model of the iPod Touch was announced by Apple, and was officially released on the Apple store on July 15, 2015. The sixth generation iPod Touch includes a wide variety of spec improvements such as the upgraded A8 processor and higher-quality screen. The core is over 5 times faster than previous models and is built to be roughly on par with the iPhone 5S. It is available in 5 different colors: Space grey, pink, gold, silver and Product (red).
ground_truth: hundred million
sub_queries: What company manufactures the iPod? Answer: Apple
How many iPods did Apple reveal it sold in April of 2007? Answer: hundred million