Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
How many kills have 15 as the injured, with a year prior to 1987?

### Inputs:
table_name: table, columns: ['Perpetrator', 'Date', 'Year', 'Location', 'Country', 'Killed', 'Injured']

### Response:
SELECT SUM Killed FROM table WHERE Injured = 15 AND Year < 1987