Significance testing over time on frequency count

Hi all,

Not sure which test I should be using. I have five years of data from one city that lists all the individuals and if their income is low, medium, or high.
If I want to test if there is a significant change over time on the number of people under each category (low, medium, or high), should I be using Chi square test?
I.e. is there significant change in the number or percentage of individuals who has high income in that city.

Thanks in advance.


Less is more. Stay pure. Stay poor.
It seems like you should be implementing time series data with the dependent variable being a rate, then looking for patterns or changes in slope. Also, do you have actual income data, that would be more telling.