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

### Instruction:
What is the sum number of year when Call of Duty 4: Modern Warfare was the game?

### Inputs:
table_name: table, columns: ['Year', 'Game', 'Genre', 'Platform(s)', 'Developer(s)']

### Response:
SELECT COUNT Year FROM table WHERE Game = call of duty 4: modern warfare