RE: Billboard charts

["Bloom, Dan" <dbloom@genesys-soft.com>]

Please forgive a list-lurker's unfamiliarity with modern-day chartmaking,
but I hope someone will take pity and help educate me, by answering my dumb,
basic, how-does-it-work question:

Decades ago the singles charts were based on consumer sales of 45s, right?
Well, what are they based on now?  Being a person who mostly listens to
radio -- generally noncomm at that -- I haven't acquired any music
recordings (well, maybe a couple LP-length cassettes) since before tapes and
CDs took over completely.  I'm unaware of "singles" for cassette or CD
players.  So what do the chart rankings for singles today actually mean?

This has long mystified me.  (Your forgiveness is also requested should I
have missed the germ of the answer in any recent posts.)  Any demystifying
would be appreciated!

	[BTW, though it's *extremely* tangential, I just saw -- and
recommend for the pop-history aficionados among you -- the new Frankie Lymon
biopic, "Why Do Fools Fall in Love"]

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