JC Penney has hit an ugly milestone that no company wants

JC Penney shares are at an all-time low, and below where they first traded publicly early in 1978.

Retailers sold off for a second day after earnings results confirmed again that the brick-and-mortar industry is in trouble.

JC Penney fell by as much as 10% on Friday to a record low of $4.73 a share. That's nearly 50% down from its debut price. The stock has been split at least twice, in the late 1980s and early 1990s.

JC Penney's first-quarter earnings released Friday showed that sales at stores open for at least one year fell 3.5% from Q1 2016, steeper than the 0.7% drop that analysts expected.

Shoppers who flocked to malls in the past are now doing most of their buying online, at places like Amazon that can be more convenient and make returning easier.

Also, some consolidation in physical retail was plausible since the US has the highest amount of retail space per person worldwide - 23.5 square feet, according to a Morningstar Credit Ratings report from October.

Over 3,000 department stores are expected to close this year.