SCHEDULE II Description Balance at Beginning of Period Additions/ (Deductions)* Write-offs Other** Balance at End of Period Allowance For Credit Losses 2018 —Current $ 594 $ 69 $ (62 ) $ (11 ) $ 591 —Noncurrent $ 74 $ (3 ) $ (2 ) $ (20 ) $ 48 2017 —Current $ 675 $ 65 $ (157 ) $ 11 $ 594 —Noncurrent $ 101 $ (10 ) $ (42 ) $ 26 $ 74 2016 —Current $ 909 $ 87 $ (307 ) $ (13 ) $ 675 —Noncurrent $ 118 $ (2 ) $ (7 ) $ (8 ) $ 101 Allowance For Inventory Losses 2018 $ 574 $ 136 $ (162 ) $ (19 ) $ 530 2017 $ 525 $ 164 $ (139 ) $ 23 $ 574 2016 $ 483 $ 178 $ (150 ) $ 14 $ 525 Revenue Based Provisions 2018 $ 451 $ 1,124 $ (1,059 ) $ (15 ) $ 500 2017 $ 481 $ 1,292 $ (1,342 ) $ 20 $ 451 2016 $ 505 $ 1,377 $ (1,392 ) $ (9 ) $ 481 * Additions for Allowance for Credit Losses and Allowance for Inventory Losses are charged to expense and cost accounts, respectively, while Revenue Based Provisions are charged to revenue accounts. Deductions represent the reversal of such charges.  ** Primarily comprises currency translation adjustments. S-1 INTERNATIONAL BUSINESS MACHINES CORPORATION AND SUBSIDIARY COMPANIES VALUATION AND QUALIFYING ACCOUNTS AND RESERVES For the Years Ended December 31: (Dollars in Millions) 