D10K problemnoun.
The concern that a future 5-digit (10,000+ points) Dow Jones Industrial Average could create problems for financial software coded to accept only 4-digit numbers.
(cf. Y2K: the Year 2000 problem.)
Example Citation:
"Curious speculation swirls around the prospect of a 10,000-point Dow Jones industrial average. At least some are concerned that the milestonethe first time the market indicator would be expressed in five digitsmight create a problem similar to the year 2000 debacle, that computers used to four-digit Dows aren't prepared to handle. It's already being dubbed the D10K problem."
June Arney, "Dow 10,000 already regarded as D10K problem for computers," The Sun (Baltimore)