Weekly Cycle

[kiwis]

I've got a series of trips taken my over a period of time. I have a start DateTime and end DateTime . 

I'm trying to place them on a timeline chart which I can do. I'm creating a new row for each week by getting the PHP week number from the date.

The issue I have is, each week start further to the right as this date is further than the previous one.

Is there a way to work around this?