This report investigates the impact of changes in definitions used for data collection in the Regulatory and Statistical Return between 2004 and 2005. The term sheltered housing was no longer used in the 2005 RSR. Instead, a new category 'Housing for Older People' was introduced. Data taken from the RSR 2004 and 2005 has been analysed to assess the overall impact the change in definition has had on stock numbers within the social housing sector.