Dear teachers,

Would you be kind enough to explain to me the proper way to interpret the expression in bold from the following sentence?

Despite its falling market share (from 13 percent in 1982 to 5 percent in 1987), Sony refused to introduce a VHS line until the late 1980s.

falling market share= share with falling prices or

falling market share = falling specific weight of goods in the market turnover

Thank you for your efforts.