Excellent Company manufactures lamps. The estimated number of lamp sales for three months are as follows:

Month Sales

August 12,000

September 16,000

October 15,000

Finished goods inventory at the end of July was 3,600 units. Ending finished goods inventory is budgeted as 30% of the next month's sales. Excellent expects to sell the lamps for $30 each. In November, sales are projected at 18,000 lamps. How many lamps should be produced in September?