These are sessions in which the ratio of the trading volume of rising issues to that of declining issues on the New York Stock Exchange is at least 9 to 1.

在这两个交易日当中，纽约证券交易所上涨股票与下跌股票的成交量之比至少都达到了9比1。

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Declining issues outnumbered advancers by a five-to-one ratio, and more than 90.0% of the trading by volume was to the downside.

FORBES: Magazine Article

This is a running total of advancing issues minus declining issues.

FORBES: Why Panic Sellers Could Be Sorry

He told them children and families' issues had become a "declining priority" in the department, despite unprecedented public concern.

BBC: Education & Family