I have been struggling with the date calculation part of tableau. I am sorry if I have been asking too many questions on this forum but I got learning tableau 5 months ago and there's so much to learn.
I have a hit wall looking at my data. My quandary is I want to look at a certain date and the dates leading up to that date and compare the same with previous year and decide what was the pattern and how has it changed this year.
For example in my sample data set I have two date columns. First is the start date and second is the running date and then there is the booked, cost price and event column. I want to arrange and visualize my data as such which will tell me for one specific START DATE starting 120 days in advance what was the price for the product and how many booked it. Even book is not a priority but the price is.
So if i am looking for one product i want to see 28th October 120 days, 100 days, 99,......1 day leading up to 28th October and do a side by side comparison for the same product last year on 28th October. What I also would like to know is how to draw a reference line on a date axis so that I can show a reference line for 28th October and see the pattern before and after. But 28th october is just an example and if the reference line can be dynamic and can be shifted that would be really amazing. So it doesn't have to be static. What can be concluded if its possible to build this view is for example there was a sporting event on 28th october 2012 so what was the demand before and after the event but the same event wasn't there last year so was the price same or more or less. I hope this all makes sense.
What I am really interested in is the Tableau wizard who is out there interested in looking at my sample and readily take on the question is to kind of take me through his ideology on how he built the view, which I can diagnose through the view.