The dataset is split into a number of time frames where each time frame hold, say, 1000 questionnaire results and each of the 18 datapoints provided in the time frame hold the fraction of the 1000 participants ticking the specific choice/question combination.

Now to calculate the correlation matrix for the dataset can I just calculate this between the 18 datapoints or do I need to consider the fact that I am dealing with 6 trinomial variables?