user: ### NOW ANSWER:
Question: Name the number of troops for troops per $1 billion being 2.45
Columns: ['Country', 'Number of Troops', '% of Total Troops', 'Troops per one million population', 'Troops per $1 billion ( USD ) GDP']
Types: ['text', 'real', 'text', 'text', 'text']
Sample row: ['United States', 74400.0, '68.216%', '291.3', '6.06']
SQL:

assistant: SELECT COUNT("Number of Troops") FROM "Table" WHERE "Troops per $1 billion ( USD ) GDP" = '2.45';