In a closely contested battle for chart honours, Justin Bieber's Love Yourself is dethroned for the second time, as compatriot Shawn Mendes's Stitches keep Canada's maple leaf flag flying at the summit.
 
Registering a ninth straight week of growth, Stitches advances 2-1 on sales of 68,125 copies, 30,517 of which were derived from streams. It swaps places with Love Yourself, whose 66,543 sales included 37,180 converted from streams.
 
Mendes is at the very beginning of his career, having only previously charted alongside The Vamps on their No.9 Simon & Garfunkel cover Oh Cecilia (Breaking My Heart) in 2014, but there are parallels to be drawn between him and Bieber. Both came to prominence via YouTube as teenagers, and both are from the province of Ontario. But Bieber was 20 before he landed the first of his three No.1's with What Do You Mean/last Autumn, while Mendes is still only 17 years, five months and 14 days old. As such, he is 25 days younger than The Netherlands' Martin Garrix was when he topped the chart with Animal in 2013,  and thus becomes the youngest No.1 male solo artist to top the chart for more than 40 years. The only younger male soloists to have No.1 hits are Little Jimmy Osmond (nine years and eight months), his brother Donny (14 years and eight months) and Paul Anka (15 years and 11 months) - the last of whom was also a Canadian teen from Ontario. Mendes' debut album - No.12 last April - climbs 49-34 (3,463 sales).
 
Two songs make their Top 10 debuts this week, and both have taken a while to get there.
 
Climbing within the Top 75 for the fifth week in a row, Snakehips' debut hit All My Friends (feat. Tinashe & Chance) jumps 11-8 (33,312 sales), while Major Lazer's Light It Up (feat. Nyla) is on the up for the fifth time in six weeks, improving 13-10 (30,48 sales).
 
Already in the Top 10, 99 Souls' Girl Is Mine  (feat. Destiny's Child & Brandy) heads north for the eighth time in nine weeks, climbing 9-5 (34,854 sales). The only time it didn't climb was three weeks ago, when it held at No.15.
 
The rest of this week's Top 10: Justin Bieber's Sorry (3-3, 51,026 sales) and What Do You Mean (4-4, 35,639 sales) and One Direction's History (6-6, 33,970) all hold their places on declining sales, while Adele's Hello rallies 8-7 (33,789 sales) and Sigala's Sweet Lovin' (feat. Bryn Christopher) falls 5-9 (31,024 sales).  
 
Exiting the Top 10 are Grace's You Don't Own Me (feat. G-Eazy, 7-11, 27,342 sales) and Coldplay's Adventure Of A Lifetime (10-13, 25,356 sales).
 
The 1975's second album, I Like It When You Sleep..., is still a month away but surrenders its third and biggest chart hit yet, as The Sound debuts at No.15 (21,042 sales). It is also instantly the highest charting of the Manchester band's nine chart hits in less than two years, replacing their introductory hit, Chocolate, which got to No.19.
 
All I Ask is the second single from Adele's 25, and jumps 188-41 to make its Top 75 debut. As it isn't available either physically or for streaming, all of its 12,315 sales are from paid-for downloads. If the chart was still on the basis of paid-for sales alone, it would be debuting at No.13.
 
Also new to the Top 75 are Jason Derulo's Get Ugly (104-57, 9,734 sales), Jonas Blue & Dakota's Fast Car (152-61, 9,493 sales), Elle King's Ex's & Oh's (89-64, 9,079 sales), G-Eazy's Me, Myself & I (feat. Bebe Rexha, 96-70, 8,012 sales) and Birdy's Keeping Your Head Up (113-75, 7,497 sales).
 
Craig David draws ever closer to his first Top 10 hit in more than seven years with When The Bassline Drops climbing 15-12 (25,554 sales). There are also new peaks for Little Mix's Secret Love Song (feat. Jason Derulo, 34-16, 20,297 sales), David Guetta's Bang My Head (feat. Sia, 21-18, 19,306 sales), Robin Schulz's Sugar (feat. Yates, 27-21, 16,954 sales), Kygo's Stay (feat. Maty Noyes, 40-27, 14,991 sales), Ellie Goulding's Army (55-35, 13,118 sales), X Ambassadors' Renegades (47-38, 12,699 sales), Zara Larsson's Lush Life (72-40, 12,333 sales), Dawin's Dessert (64-44, 12,024 sales), Alessia Cara's Here (69-49, 11,222 sales) and Charlie Puth's One Call Away (75-56, 9,870 sales),   
 
A No.8 hit in December, Nathan Sykes' second solo hit, Ove And Over Again is now available as a duet with Ariana Grande. The new version provides most of the sales that power the song 124-54 (10,078 sales), although Grande hasn't received a chart credit for her assistance.
 
David Bowie material is making a much faster fade on the singles chart than on the albums chart, after the surge precipitated by his death. He had 30 songs in the Top 200, and 11  in the Top 75 last week. Now, he has 17 in the Top 200, and six in the Top 75. Those that remain in the Top 75 are Heroes (12-30, 14,006 sales), Life On Mars (16-32, 13,769 sales), Starman (18-36, 12,980 sales), Let's Dance (23-47, 11,4096 sales), Space Oddity (24-51, 10,743 sales) and Changes (49-73, 7,665 sales).  
 
Overall singles sales are down 0.56% week-on-week at 8,552,720. Streams accounted for 6,578,157 sales - 76.91% of the total. Paid-for sales are down 8.89% week-on-week at 1,974,563 - 24.44% below same week 2015 sales of 2,613,098 and the 128th week in a row that they have fallen versus a year earlier.

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