I'm working with employment data to compare my local region with Pennsylvania's employment as a whole. I'd like to determine whether differences from the overall ratio are significant,

e.g. my region has 20.23% of PA's 5,426,530 jobs. But in, say, the Air Transportation sector, we have 4,445 of PA's 11,619 jobs, or 38.26%. That seems like a significant difference. But since the two ratios are dependent and just one number each instead of a set of observations, I don't know how to determine it statistically.