The chip index closed 20.2 percent below its June record, which is the bear market line

11,673.89. That is where the PHLX Semiconductor Sector Index closed on Friday, down 193.61 points, or 1.63 percent, on the index publisher's own page. The index carries 30 constituents. It reached 11,939.44 at the session high and 11,194.60 at the low, a range of more than 6 percent between the two, which is a wide day for a benchmark of this size and was not resolved until the close.

Measured against its record closing high, set on June 22, Friday's close leaves the index down 20.2 percent, reported by Panos Mourdoukoutas at The Epoch Times. Twenty percent is the conventional line at which a drawdown is called a bear market.

The rest of the tape fell less. The S&P 500 closed at 7,457.69, down 76.08 points or 1.01 percent, the Nasdaq Composite at 25,520.24, down 361.70 or 1.40 percent, and the Dow Jones Industrial Average at 52,146.42, down 406.55 or 0.77 percent, according to Grace O'Donnell, Jake Conley and Ines Ferré at Yahoo Finance.

A 20 percent drawdown is a definition rather than a diagnosis. It compares two closing prices and says nothing about why they differ. No exchange, issuer or index publisher stated a cause for Friday's session, and none is asserted here.