In 2018, Statistics Canada changed how the Census Family Low Income Measure was calculated. Two new papers explain the use of the Low Income Measure from the T1 Family File.

The first paper, “Methodology Changes: Census family low income measure based on the T1 Family File” summarizes methodological changes to the LIM calculated using the T1FF that were introduced this year. From this page, you can access updated data tables (data from 2004 to 2015) or the paper. CDP is looking into how these changes impact the program's existing holdings of T1FF low income tables.

The second paper, “Low Income Measure: Comparison of Two Data Sources, T1 Family File and 2016 Census of Population”, explains differences between T1FF LIM (calculated based on the latest methodology changes) and Census LIM data. It looks at differences in after-tax low income measure (LIM) statistics from two data sources which both use administrative tax data as their principal inputs: the 2016 Census of Population and the T1 Family file (T1FF). It presents a summary of the two data sources and compares after-tax LIM statistics by focusing on unit of analysis, LIM thresholds and the percentage of population below the LIM. The study also explores what factors users may want to consider when choosing one data source over the other.