Warning: this chart is a bit tough to digest. But we'll walk you through it with a few bullets. At a PE of around 17x, the S&P 500's valuation is arguably on the high side. But the history since ...

But one chart from his August 1 offered some eyeopening perspective. Here's his comment for context: In the late 1990s, the TMT bubble expanded, with the combination of the IT sector along with ...