Question: is a year qualitative or quantitative?
Answer: Year can be a discretization of time. For example, you might have data for a child's height on January 1 of years from 2010 to 2018. It's meaningful to ask for height at (say) 2013.5, that would just be on June 30, 2018. So year is a discretized measure of a continuous interval variable, so quantitative.