Young Brunette Girl Wearing Black Stockings

In 1953, Allen Gant Sr. of Glen Raven Knitting Mills developed a commercial equivalent named "Panti-Legs", but didn't bring it to market until 1959. The introduction of pantyhose in 1959 provided a convenient alternative to stockings, and the use of stockings declined dramatically. During the 1960s, improved manufacturing made pantyhose cheaper, spandex (or elastane) made them more comfortable, and the miniskirt made them a fashion necessity. In 1970, U.S. sales of pantyhose exceeded stockings for the first time, and has remained this way ever since.
The popularity of pantyhose grew into a wardrobe staple throughout the 1970s and '80s. It wasn't until 1995 that a steady decline in pantyhose sales began, leveling off in 2006 with U.S. sales less than half of what they had been. This decline has been attributed to bare-legged fashion and changes in workplace dress code. The cost of stockings and pantyhose and the easy snagging and runs was another factor against sheer hosiery. Besides going bare-legged, there has also been a shift towards trousers and leggings or footless tights, the advantage of which is that they do not run like traditional stockings. The slide in sales is expected to continue into the future.
The word stock used to refer to the bottom "stump" part of the body, and by analogy the word was used to refer to the one-piece covering of the lower trunk and limbs of the 15th century—essentially tights consisting of the upper-stocks (later to be worn separately as knee breeches) and nether-stocks (later to be worn separately as stockings).