I am trying to figure out how to calculate if a survey statistic is different from a benchmark or goal. The statistic is a little different than normal, because the survey question has 3 options: positive/neutral/negatives. The statistic I am using is basically the "net positive" where I take the sum of all the positive responses minus the sum of all the negative responses, divided by the number of responses (Pos-Neg)/N

I'm not exactly sure how to go about trying to figure out if the statistic is different from the goal. For example, if I survey a population and I get back 90 positive responses and 10 negative responses for this survey, which gives me a "net positive" score of 80%, how would I say if this is statistically different from a goal of 70%?