The phrase "percent slide" refers to a decrease in something, usually expressed as a percentage. It means that there has been a decline or drop in a particular quantity or value compared to its previous level. Full definition
While the dive in oil prices has been a major drag on financial markets, the 55 percent slide in crude oil prices since June is good news for some. (cnbc.com)
The bookseller announced a 34 percent dip in revenue year - over-year for its Nook division during the fourth quarter and reported a nearly 17 percent slide for the year. (pcworld.com)
Other declines of similar size include a 5.875 percent cut from 1983 - 1986, and more recently, a 5.5 percent slide from 2000 - 2003. (hsh.com)