Deere & Company manufactures, distributes, and finances a full range of agricultural equipment; a broad range of industrial equipment for  construction, forestry, and public works; and a variety of lawn and grounds care equipment. The company also provides credit, health care, and insurance products for businesses and the general public. Consider the following information from the Deere & Company 2000 Annual Report:

(in millions)

1997

1998

1999

2000

Sales

$12,791

$13,822

$11,751

$13,137

Cost of goods sold

8,481

9,234

8,178

8,936

Gross margin

4,310

4,588

3,573

4,201

Operating expenses

2,694

2,841

3,021

3,236

Net operating income

$ 1,616

$ 1,747

$ 552

$ 965

a. Prepare a statement showing the trend percentages for each item using 1997 as the base year.

b. Comment on the trends noted in part (a).