XY chart, week number position

I have 3 entries, with x,y (t_stamp, value)
When I set date format on x to “w” (week number), the week show up inbetween the columns.
How do I get them placed directly under the columns ?

I am aware that this is a range, and therefore might need some additional calculation like -1 week or something like that, to be able to place the weeks correctly.