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

### Instruction:
How many regions had rainfall infiltration (km 3/year) of 9.3?

### Inputs:
table_name: table, columns: ['Region', 'Land area (km 2 )', 'Rainfall by depth (mm/year)', 'Rainfall by volume (km 3 /year)', 'Surface run off (km 3 /year)', 'Infiltration (km 3 /year)', 'Evapotranspiration (km 3 /year)']

### Response:
SELECT COUNT Rainfall by depth (mm/year) FROM table WHERE Infiltration (km 3 /year) = 9.3