Public Law 116-94, Division Q, Section 103 changed the medical deduction floor percentage from 10% to 7.5% for 2020. We changed the percentage in the text on line 1 of the Step 4(b)-Deductions Worksheet on page 3 of the 2020 Form W-4 to 7.5%. We also made one minor editorial clarification on line 4 of that worksheet changing "from Schedule 1" to "from Part II of Schedule 1". The revised form became available on December 31, 2019. You may still use copies of the form printed or downloaded before December 31, 2019, but those forms will have the wrong 10% percentage shown (which only impacts a few people, and the impact is likely to be very small if any and can be mitigated by using the Tax Withholding Estimator after it is updated for this change and/or using the new revision of Form W-4 with the 7.5% amount).