Title: Impact of atypical weather of seasonal adjustment
Authors: Susie Fortier - Statistics Canada (Canada) [presenting]
Steve Matthews - Statistics Canada (Canada)
Zdenek Patak - Statistics Canada (Canada)
Abstract: One of the challenges of seasonal adjustment is unseasonal events such as weather extremes. It is conceivable that long stretches of unusually low or high temperatures, prolonged drought conditions, extended rainfall, to name a few, may impact the behaviour of both individuals and businesses. Seasonal adjustment removes repeating, equally spaced patterns from the corresponding time series data, along with movement due to various holidays and other predefined regressors, but it does not remove the impact that atypical weather may have. To fill the void, many national statistical agencies have been studying the use of weather related indicators in their time series analyses, including seasonal adjustments. We discuss alternatives for incorporating the data into seasonal adjustment and ad hoc analysis.