I'm sure my problem is laughably simple, but I really need help! This is very much out of my skill level.
I have two sets of data: 2015 and 2016 data for ER vist counts for different syndromes (asthma and general respiratory) and particulate matter pollution levels. I want to know the relationship of PM2.5 on ER visits, specifically, is there any difference between the 2015 and 2016 data and if so, is it statistically signficant?