Statistics is not a normal part of my job. I've been given survey data from three years. Survey data includes a number of categories the respondents are split into. There is a set of five possible responses for each. Each year, the percentage of each response for each category is calculated. I need to provide a three year average for each response for each category.
Which method do I use to calculate the three year average for each category?
- Add the raw totals from each year for each response and divide by the total respondents over the three years.
- Add the three single-year percents, then divide by 3 to get an average percent.
I can provide example data if that would be helpful.