How do I create a chart that only shows data for the past 6 weeks for example? I have a weeknum column and I've put this column on the x-axis of the charts.
At the moment, the chart shows all week numbers that exist in the data and will continue to build when more data is inputted. So over time this will get cramped hence why i only want to show the past 6 weeks.
If your week number is being derived off some sort of date field, what you can do is put the date field in the visual filter section and use the relative date filtering to say you're only wanting data within the last 42 days. Not sure how it would work if it isn't, perhaps make some sort of calculated column that has a week number running continuously (so that it doesn't reset year on year), then look up the largest value (to get the current week number), and do some DAX to take that off of your new column, add six, then filter on positive values?
This is similar to the previous suggestion, but the same issue occurs. It takes the latest [#] weeks from today's date. But if the data is not up-to-date, then it doesn't work so well. In my case, the latest data date is 16/01/2018, and if I choose to show the last 6 weeks, it only shows me 3 weeks. If i choose to show the last 1 week, it appears as blank as i don't have any data for the past week.