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HPMS Data Library


Our workshops and conferences demonstrate our efforts to keep communication open and remain accessible to our partners and shareholders. We will continue to document discussions between stakeholders and share the outcomes as we move ahead and improve our processes.



In July of 2004, a study was done comparing the methodology in a number of states as to how IRI data is gathered. A survey was taken and 39 states responded with information about the methods, locations and frequency for collecting IRI data. The results of the survey are summarized in an Excel file.


Other Data and Information


For information on file formats and how to download them:

Simple instructions as needed.

Page Updated on February 8, 2017