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

### Instruction:
What was the largest number of aggravated assaults when there were 3811 robberies?

### Inputs:
table_name: table, columns: ['Year', 'Population', 'Index', 'Violent', 'Property', 'Murder', 'Forcible rape', 'Robbery', 'Aggravated assault', 'Burglary', 'Larceny Theft', 'Vehicle Theft']

### Response:
SELECT MAX Aggravated assault FROM table WHERE Robbery = 3811