how has the proportion of data changed over a time period how does the ratio of a period change over time how does the proportion of time change how has the a/b relationship changed over time how has the proportional ratio changed over time how has the a/b ratio changed over time? what is the relationship between the proportion and the a/b how does the a/b r relationship change from a time period to the next how has the proportional ratio changed over time how has the proportion of b changed over time? how long does a ratio change over time how has the a/b ratio changed over time how does the proportion in the a/b ratio change how does data proportion change over time? how has a relation of a time period changed can i test whether the a/b of the time series has increased over time? how is the proportion of time related to the period how has the a/b changed in the data over time? how is a/b a significant change how has a dp time r relationship changed over time