Global GPS Systems manufactures rugged handheld GPS computers for use in adverse working environments. Global tries to maintain inventory at 30% of the following month's expected unit sales. Global began the year with 15,000 units in stock based on the following units sales projections prepared by the sales manager:

january 30,000

february 37,500

march 27,000

april 33,000

Prepare a schedule of planned unit production budget for january through march.