user: Question: How many security forces?
Columns: ['Period', 'Civilians', 'Security forces', 'Insurgents', 'Total per period']
Types: ['text', 'real', 'real', 'real', 'real']
Sample row: ['1989–2001', 1610.0, 432.0, 1007.0, 3049.0]
SQL:

assistant: SELECT SUM("Security forces") FROM "Table";