The 2013 data collection period was characteristic of a typical year (late April through September). However, the 2011 AHS data collection period was delayed three months due to budgetary reasons (data were collected from July through December).

As a result of this shift in collection months, respondents in 2013 were asked to report the home improvement projects they had done in the past two years, which overlapped with the 2011 collection months. It is important to note that this overlap would only occur for housing units that were previously included in the 2011 survey; housing units that were new to the 2013 sample would be unaffected by this shift in collection period.