in the red

in the red  {adv.} or  {adj. phr.},  {informal}

In an unprofitable way; so as to lose money.

A large number of American radio stations operate in the red.

A rich man who has a farm or ranch often runs it in the red, but makes his money with his factory or business.

Contrast: IN THE BLACK.

Origin: From the fact that people who keep business records usually write in red ink how much money they lose and in black ink how much money they gain.