International Paper's stock slumped by $1 a share, to $36.125.
The stock has slumped more than 30 percent since August.
Its stock had slumped because of a recession in the oil industry.
Disney's stock has slumped by about a third from its 1998 high of just over $42.
But the stock has since slumped to $120.50, including a decline of $10.50 yesterday.
Robbins sold the shares at 404.5p eight days before the stock slumped to 316p.
The final issue price was $4.10, but by August 2011 the stock had slumped to as low as $2.09.
In other words, when stocks and bonds slumped, commodities did not.
Stocks slumped during the day on the prospect of higher borrowing costs.
Digital's stock hit a peak of $199.50 in 1987, but has slumped badly since then.