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 15000 units in stock, based on the following unit 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.