how do you compare ages and groups average age to age how to calculate age and group differences how to calculate a change in ages how to find difference in ages across time calculate the age of two groups of individuals what's the difference between age and age? how do i find age of individuals on the same variable how to find the difference between two groups across time how do you compare age and age how do you find the age differences between two groups how to find the difference between groups and across time which variable is used to determine differences from one group and over time? how to determine if a variable is a difference in time across time? how to calculate the difference between two groups and between time periods which variable does a variable in ARIMA model have a significant difference across time how does a swap measure the difference what is the difference between groups over time predicting the age differences between a group of individuals what is the difference between time and age