It would be interesting though maybe not very valuable to see what the indexes would look like projected forward at their '80s form by company content before "xyz" corp was removed to be replaced by "abc" corp. over time. Or at 5 year intervals or some other marking point.
I would have to hypothesise that the current crisis in the financial and consumer markets would have been telegraphed in some more aggressive fashion if the indexes bad performers hadn't been removed and replace with the new breed of good guys. Sort of like regularly buying clothes just a little bit bigger to mask the fact that I'm gaining weight at an unsustainable rate. Just a guess... If is was an economist, I'd be looking for signs that reflected when the consumer could not sustain their consumptions without borrowings increasing in size and regularity...which imo were the sparks beginnings of this forest fire of an end.
Probably a great topic for an Economics PhD thesis...available here at no charge.
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