Русско-англо-русский юридический словарь

1. investment /ɪnˈvɛsmənt/ US (in something; как общее понятие);

• иностранные инвестиции – foreign investment

• прямые инвестиции – direct investment

• прямые иностранные инвестиции – foreign direct investment

2. investments (in something; как серия отдельных инвестиций);

Примеры употребления

That year, Japanese investment in American real estate totaled $13.06 billion. (Longman English Dictionary)

'Investments' would be a series of individual investments. 'Investment' would be the process or concept as a whole, used if you're talking about the generality of investment. (English Forums)

Interest rates will be cut on short-term investments. (Longman English Dictionary)