How can I use the PPI to track client poverty over time?

Administer the PPI to the same group of households or two equally representative samples of households at a regular interval. If an individual household’s poverty likelihood changes, you can infer that the household’s economic standing has changed. For example, if a household had a 65% likelihood of living below the poverty line last year and a 54% likelihood of living below the poverty line this year, you can infer that the household is moving towards being non-poor.

If the poverty rate of a group changes over time, you can infer that the number of people in the group who live below the poverty line has changed. For example, suppose last year 58 percent of your clients lived below the poverty line. Then suppose that this year only 39 percent of the same group of clients lived below the poverty line. This means that every 19 out of 100 clients moved out of poverty.