
Since T, dubbed by the publisher as "the biggest newspaper launch in 30 years", it has been the biggest-selling newspaper in the market.
The Sun on Sunday achieved an average circulation of more than 2.4m in its first full month (March 2012), outselling its closest rival by around 600,000 copies.
Advertising space for the first issue was reported to have sold out within two days of announcing its launch, and brands including Sky, 02, Weight Watchers and William Hill now regularly appear in each edition.
However, the tabloid has yet to stabilise copy sales since its bumper launch issue attracted 3.2 million.
Figures released on Friday (11 May) highlight , with average circulation down 5.3% to 2,297,441 copies.
Average weekly sales have now slipped well below those enjoyed by News International’s former Sunday tabloid, News of the World, which stood at 2.66 million in June 2011, the month before it was closed amid phone hacking allegations.
Circulation for the Sunday edition of The Sun remains more than double that of its redtop rival Sunday Mirror, and the product is said to be commercially strong, with its Fabulous supplement attracting a host of new advertisers, including Aciete de Olivio, Ikea, Vimto, PZ Cussons and CSL Sofas.
Yet the Sunday Mirror's cover price of £1 is twice as high as The Sun's 50p, so any revenue from copy sales between the two titles are currently largely the same. There are fears among some media agencies that the reach of The Sun on Sunday could shrink further if its cover price increases, as it is widely tipped to do following its launch offer.
Paul Hayes, managing director of News International Commercial, said: "Ten (10) weeks in and the Sun on Sunday is continuing its success story with both readers and advertisers backing the Sunday edition, and in some instances we are seeing advertisers increasing their YOY spend within the Fabulous magazine.
"We offer a genuine seven day proposition that will give advertisers more reach, creative opportunities and flexibility than ever before."
According to The Sun on Sunday Readership Study (IPSOS Media April 2012) of the estimated total seven day reach of The Sun (15.3m), 13% only read the Sunday edition, equating to nearly 2m adults.
Looking deeper into the demographics of the newspaper, it attracts more female readers than its Monday-Saturday edition (49% compared to 42%) and the audience for the Sunday edition also skews younger (43% on Sunday compared to 35% Monday-Saturday). The average readers per copy is also higher, which reflects the high level of interest.
The content of the tabloid, confirmed during the ongoing Leveson Inquiry as being closely aligned to the views of News Corporation chairman Rupert Murdoch, is designed to be more family-friendly on Sunday, with nipples being covered up on its famous Page 3.
The move appears to be working, with Dominic Mohan, editor of the Sun on Sunday, noting it was attracting "a younger, more female audience who enjoy the family-focused content".
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