Apr 14 2021 01:09 PM
Apr 14 2021 02:08 PM
Enter 01/01/2021 in a cell (for example in another workbook).
Change the number format of that cell to General.
You'll see the number 44197. This is how Excel stores 01/01/2021 internally.
Do the same for 12/31/2021. The corresponding number is 44561
Now double-click an x-axis label again.
Under Axis Options, set Minimum to 44197 and press Enter.
Then set Maximum to 44561 and press Enter.