跨国并购

UNCTAD M&A 数据库 以Value of net cross-border M&As by region/economy of purchaser, 1990–2021 统计的数据，出现负数是什么意思呢，跨国并购的购买额为负数

数据后面有注明吧
Divestments (sales of foreign affiliates to domestic firms) are subtracted from the value (number)