I am a student currently learning Tableau. I use Tableau for Teaching 18.2. I have a question regarding a line chart. I have a 3x3 table (male, female, total / 2005, 2012, 2016) and only the value of 2016 are significantly different from 2012. Thus, I want to have a dashed line connecting 2005 with 2012 but a full line connecting 2012 and 2016. I already use a dual axis to have markers of the data points in my visualisation. How would I do that? First of all: I do not really understand how to change the pattern of the line chart at all as it gives me the option of trend line, dropping line, grid line etc. but not the actual data line. Second: As I only want a sequence changed, so 2 patterns within the same line, how would I do that? I thought of a dual axes but then I'd lose my marker points and the legends would be doubled.
Thanks a lot for your help!