I have a simple table of survey data arranged in rows with one resonse per row, the total number of rows equalling the total number of reponses. There is a Year column containing either 2015 or 2016 and a question column indicating the survey question. I want to be able to calculate the difference in the number of responses (rows) between 2015 and 2016 for each question, or group of questions.
I then want to plot the year on year difference on a graph where a decrease shows beneath the X axis. I guess I need to create a measure but can't find any help in how to do this. Can you help??