Ask Billboard is updated every Friday. As always, submit your questions about Billboard charts, sales and airplay, as well as general music musings, to email@example.com. Please include your first and last name, as well as your city, state and country, if outside the U.S.
'SPEAK'-ING OF SWIFT
I wanted to weigh in on the discussion regarding Taylor Swift  and the "Glee"  cast's accumulation of hits that sell well enough digitally to place high on the Billboard Hot 100  chart and then tumble off within a week or two.
While it may be a different way of achieving a top 10 or top 20 hit than it was just more than five years ago and before, these abbreviated runs have been commonplace since Nielsen SoundScan data revolutionized the Billboard 200 in 1991, and I've never heard anyone begrudge John Mellencamp , Heart, Weezer, Mariah Carey , Christina Aguilera , Bob Dylan or any of the other dozens of artists from just the past two years who have placed an album in the top 10 and then dropped entirely out of the top 40 of that chart the following frame.
Record charts are, and have always been, greatly influenced by the popularity of that particular piece of music in any given week. A chart is not a ranking of the overall popularity of the act that performs the song over a given amount of time, and it's not a gauge of how "credible" someone might find the particular artist who performs the piece.
It is easy to bash "American Idol" contestants, or "Glee" cast members or even superstar acts who appeal mostly to the tween/teen set by picking apart the longevity of their chart runs. But, many of the artists who had hits in years past still find it difficult to create, record and release an album that can log a lengthy chart run. If anyone can sell well enough to beat out 90 or 95% of the songs or albums on a chart, then guess what: they've earned a top 10!
I applaud Billboard for sticking to your guns on this issue and not changing any rules that would keep these hot acts of the day from earning their place in music history. Let's give these newer acts credit for accumulating their hits.
Michael Marquardt, Sr.
Thanks for your e-mail. For a deeper discussion of the chart arc of recent such songs, including my earlier take on the topic, please check out last week's Ask Billboard (Nov. 5) .
I agree that the Hot 100 continues to serve the same purpose it has since its launch in 1958: to show the best-selling and most-heard (and now, most-streamed, as well) songs in the U.S. each week. As for songs that chart high because of mostly only airplay or mostly only sales, we also feature a wide variety of genre airplay and digital charts to further breakdown songs' popularity on different levels.
Certainly, there's room for endless analysis of what makes a hit song. The Hot 100's archives are filled with titles that peaked at low positions and are well-remembered and others that reached lofty levels and are now considered obscure. It's that human element - which songs we still buy, listen to and discuss more than others - that make our charts not just impersonal statistical listings, but truly pop culture, and personal, diaries that can inspire emotion with every view.
EXCLUSIVE ADULT CLUB
With lengthy stays at No. 1 this year for Lady Antebellum 's "Need You Now" and Train 's "Hey Soul Sister" on the Adult Contemporary  chart, has this chart year seen the fewest No. 1s of any year?
As always, adult contemporary programmers have been sticking to the biggest adult hits available in 2010, as just five titles have risen to No. 1, including the latest this week:
Weeks At No. 1, Title, Artist, Peak Date
3, "Haven't Met You Yet," Michael Buble, Jan. 30
5, "Fallin' for You," Colbie Caillat, Feb. 6
15, "Need You Now," Lady Antebellum, April 3
18, "Hey, Soul Sister," Train, July 3
1 (to-date), "Breakeven," the Script, Nov. 20
Train's 18-week reign with "Hey, Soul Sister" ranks among the 10 longest in the chart's 49-year history and Lady Antebellum's 15-week command with "Need You Now" is the longest by a country group.
This year's quintet of leaders does not mark the lowest yearly sum on Adult Contemporary, but it's close. Five songs also ascended to No. 1 in each of 2008 and 2009, although in 2008, just four had reached the summit between January and mid-November.
The year with the fewest No. 1s was 2005, when a mere four songs rose to the top:
Weeks At No. 1, Title, Artist, Peak Date
21, "Breakaway," Kelly Clarkson, March 12
2, "Home," Michael Buble, July 30
18, "Lonely No More," Rob Thomas, Aug. 20
4, "Up on the Housetop," Kimberley Locke, Dec. 17
THANK U, IN ADVANCE
I have been listening to my collection of Alanis Morissette  albums a lot lately - even her more recent ones - and I was wondering if you could please tell me how many copies she has sold of each.
I have been a big fan of hers for almost 10 years now (I was only seven when "Jagged Little Pill" was released!) and I miss the days when she was one of the best-selling female artists in the world! Reading about Taylor Swift's success reminds me of how big Alanis was in the '90s.
I was working at radio station WBMX/Boston  in the mid-'90s when Morissette was scoring hit after hit from "Jagged Little Pill." As the station played CDs then (many radio station libraries now are computerized), that album almost never made it back into the wall's CD rack, since "You Learn," "Ironic" or "Head Over Feet" played so much.
Here is a look at Morissette's U.S. album sales, according to Nielsen SoundScan, as well as their Billboard 200 peaks:
14,668,000, "Jagged Little Pill," 1995 (No. 1, 12 weeks)
2,602,000, "Supposed Former Infatuation Junkie," 1998 (No. 1, 2 weeks)
1,019,000, "Under Rug Swept," 2002 (No. 1, 1 week)
651,000, "MTV Unplugged," 1999 (No. 63)
472,000, "So-Called Chaos," 2004 (No. 5)
373,000, "The Collection," 2005 (No. 51)
372,000, "Jagged Little Pill: Acoustic," 2005 (No. 50)
229,000, "Flavors of Entanglement," 2008 (No. 8)
76,000, "Feast on Scraps," 2002 (No. 194)
Morissette has sold 20.5 million albums in the U.S., with "Jagged Little Pill" ranking as the third-best-selling set since SoundScan began tracking sales in 1991.
I like her more recent work quite a bit, as well, with "Not as We," from "Flavors of Entanglement," featuring the touching post-breakup lyrics: "Day one, day one, start over again / Step one, step one, I'm barely making sense / For now, I'm faking it, 'til I'm pseudo-making it / From scratch, begin again, but this time I as 'I,' and not as 'we'."
While Morissette is no longer signed to Warner Bros. Records, she has remained in the public spotlight this year, having performed on the May 26 season finale of "American Idol," joining eventual runner-up Crystal Bowersox for a duet of "You Oughta Know." Morissette also contributed a new song, "I Remain," to the "Prince of Persia: The Sounds of Time" soundtrack.
This year has brought infinitely more rewarding personal news for the singer. Four days before her "American Idol" appearance, Morissette married rapper Mario "MC Souleye" Treadway. The happy pair is expecting their first child, as this picture  clearly illustrates.
- Chart Beat