1. In practice, the Producer Price Index (PPI) program uses a formula closer to a Young formula at the elementary level and a formula closer to a Lowe formula at higher levels of aggregation.
2. 2 Price-index research often refers to weights rather than quantities. These weights are calculated with quantity data, whereby base-period quantities are multiplied by base-period prices to arrive at base-period revenue weights.
3. 3 Specifically, the PPI program uses a geometric Young formula to calculate the PPI geomean research series.
4. 4 Kenneth V. Dalton, John S. Greenlees, and Kenneth J. Stewart, "Incorporating a geometric mean formula into the CPI," Monthly Labor Review, October 1998, https://www.bls.gov/opub/mlr/1998/10/art1full.pdf.
5. 5 Jonathan C. Weinhagen, "Measuring the substitution effect in Producer Price Index goods data: 2002-16," Monthly Labor Review, July 2020, https://doi.org/10.21916/mlr.2020.16.