when is utility retrofit data available when to compare time series for utility bill when can i compare the data between pre retrofit and post retrofit? how do you compare the time periods for utility retrofits how many years does a utility bill last when comparing utilities between pre retrofit and post retrofit comparison of utility retrofit data how to compare utility bill times when do you compare utility bills when do you compare pre retrofit utility bills how do i compare utility bill data to post retrofit how many years is utility bill data before retrofit what is the difference between a pre-retrofit bill and post retrofit? how to compare time series utility bills can i compare utility bill data to retrofit time series utility bills how do you compare pre retrofit utility billing how to compare utility bill data before retrofit can you compare time series on utility bill what is utility bill time series