The following table shows net sales by reportable segment for 2022, 2021 and 2020 (dollars in millions): Net sales by reportable segment: Americas Europe Greater China Japan Rest of Asia Pacific Total net sales 2022 Change 2021 Change 2020 $ 169,658 11% $ 153,306 23 % $ 124,556 95,118 7% 89,307 30 % 68,640 74,200 9% 68,366 70% 40,308 25,977 (9)% 28,482 33 % 21,418 29,375 11 % 26,356 35% 19,593 $ 394,328 8% $ 365,817 33 % $ 274,515 Gross Margin Products and Services gross margin and gross margin percentage for 2022, 2021 and 2020 were as follows (dollars in millions): Gross margin: Products Services Total gross margin Gross margin percentage: Products Services Total gross margin percentage 2022 2021 2020 $ 114,728 $ 105,126 $ 69,461 56,054 $ 170,782 $ 47,710 152,836 $ 35,495 104,956 36.3% 35.3% 31.5% 71.7% 69.7% 66.0% 43.3% 41.8% 38.2% Operating Expenses Operating expenses for 2022, 2021 and 2020 were as follows (dollars in millions): Research and development 2022 $ 26,251 Change 2021 Change 2020 20% $ 21,914 17% $ 18,752 Percentage of total net sales 7% 6% 7% Selling, general and administrative $ 25,094 14 % $ 21,973 10% $ 19,916 Percentage of total net sales 6% 6% 7% Total operating expenses $ 51,345 17% $ 43,887 13 % $ 38,668 Percentage of total net sales 13% 12% 14%