How do you do these calculations? I don't think I am doing them correctly.

Dec 31, 2020 Dec 31, 2019 $ 42,122 42,274 23,795 24,542 132,733 113,114 37,553 15,017 22,778 321,195 $36,092 18,929 20,497 20,816 96,334 72,705 25,141 14,754 16,314 : 225,248 1 Consolidated Balance Sheets - USD ($) $ in Millions 2 Current assets: 3 Cash and cash equivalents 4 Marketable securities 5 Inventories 6 Accounts receivable, net and other 7 Total current assets 8 Property and equipment, net 9 Operating leases 10 Goodwill 11 Other assets 12 Total assets 13 Current liabilities: 14 Accounts payable 15 Accrued expenses and other 16 Unearned revenue 17 Total current liabilities 18 Long-term lease liabilities 19 Long-term debt 20 other long-term liabilities 21 commitments and contingencies (Note 7) 22 stockholders' equity: Preferred stock, $0.01 par value: Authorized shares - 500 Issued and outstanding shares - 23 none Common stock, $0.01 par value: Authorized shares - 5,000 Issued shares - 521 and 527 24 Outstanding shares - 498 and 503 25 Treasury stock, at cost 26 Additional paid-in capital 27 Accumulated other comprehensive income (loss) 28 Retained earnings 29 Total stockholders' equity 30 Total liabilities and stockholders' equity. 72,539 44,138 9,708 126,385 52,573 31,816 17,017 47,183 32,439 8,1901 87,812 ! 39,791 23,414 12,171 0 0 5 5 i (1,837) 42,865 (180) 52,551 93,404 $ 321,195 (1,837) 33,658 (986) 31,220! 62,060 $ 225,248 1 2 3 4 5 HORIZONTAL ANALYSIS ABC Comparative Balance Sheets For the Years Ending December 31 Current Year (CY) 6 Prior Year (PY) Percentage Difference (PY- (CY - PY)/PY 2YP)2YP 2 Years Prior (2YP) 7 8 Current assets Long-term investments Property, plant, & equipment Intangible assets Other assets Total assets 132733 197510 113114 15017 22778 96334 127726 72705 14754 16314 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Current liabilities Long-term liabilities Total liabilities 126385 101406 87812 75376 Paid-in capital Retained earnings Treasury stock Total stockholders' equity Total liabilities & stockholders' equity 52551 -1837 93404 31220 -1837 62060 23 321195 225248 Dec 31, 2020 Dec 31, 2019 $ 42,122 42,274 23,795 24,542 132,733 113,114 37,553 15,017 22,778 321,195 $36,092 18,929 20,497 20,816 96,334 72,705 25,141 14,754 16,314 : 225,248 1 Consolidated Balance Sheets - USD ($) $ in Millions 2 Current assets: 3 Cash and cash equivalents 4 Marketable securities 5 Inventories 6 Accounts receivable, net and other 7 Total current assets 8 Property and equipment, net 9 Operating leases 10 Goodwill 11 Other assets 12 Total assets 13 Current liabilities: 14 Accounts payable 15 Accrued expenses and other 16 Unearned revenue 17 Total current liabilities 18 Long-term lease liabilities 19 Long-term debt 20 other long-term liabilities 21 commitments and contingencies (Note 7) 22 stockholders' equity: Preferred stock, $0.01 par value: Authorized shares - 500 Issued and outstanding shares - 23 none Common stock, $0.01 par value: Authorized shares - 5,000 Issued shares - 521 and 527 24 Outstanding shares - 498 and 503 25 Treasury stock, at cost 26 Additional paid-in capital 27 Accumulated other comprehensive income (loss) 28 Retained earnings 29 Total stockholders' equity 30 Total liabilities and stockholders' equity. 72,539 44,138 9,708 126,385 52,573 31,816 17,017 47,183 32,439 8,1901 87,812 ! 39,791 23,414 12,171 0 0 5 5 i (1,837) 42,865 (180) 52,551 93,404 $ 321,195 (1,837) 33,658 (986) 31,220! 62,060 $ 225,248 1 2 3 4 5 HORIZONTAL ANALYSIS ABC Comparative Balance Sheets For the Years Ending December 31 Current Year (CY) 6 Prior Year (PY) Percentage Difference (PY- (CY - PY)/PY 2YP)2YP 2 Years Prior (2YP) 7 8 Current assets Long-term investments Property, plant, & equipment Intangible assets Other assets Total assets 132733 197510 113114 15017 22778 96334 127726 72705 14754 16314 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Current liabilities Long-term liabilities Total liabilities 126385 101406 87812 75376 Paid-in capital Retained earnings Treasury stock Total stockholders' equity Total liabilities & stockholders' equity 52551 -1837 93404 31220 -1837 62060 23 321195 225248