Proposal of data analysis
Hello, I'm an undergrad student in my final year of an art sci degree.
I’ve been given the assignment to come up with a research proposal of my choice. Unfortunately, I have reached a wall in my proposal.
To give an idea of what my proposal thus far is:
I am interested in looking at the possible negative effects smoking bans have had on bars. Research thus far has been fairly convincing that there are no negative impacts on bar revenue due to these smoke free laws.
It has been suggested though that climate (cold weather) could lead to there being a negative impact.
The study I am proposing is to look at Ontario bars, there was a province wide implementation of the such a law in 2004.
Where my problem is this, I do not know what type of analysis I should use to determine if there has been an impact.

I have monthly data on a municipality scale for :
-climate, average monthly evening temp
-a measure for bar revenue
(total bar rev./ total retail sales– bar rev.)

I have this data available for every month for the past 8 years.
My question is a three parter,
a. Can I keep each municipality separate or should I combine them into categories such as Temp ranges
b. What kind of analysis do I apply
c. Which method would be best suited to answer my research question [does a colder climate exacerbate the effects of smoke free legislation on the revenues of bars?]

Please don’t hesitate to ask for more details on what I am trying to do as I am quite aware that I have given a fairly vague description.
All help is greatly appreciated, thank you in advance.