Highway Safety Information System (HSIS)HSIS is a roadway-based system that provides quality data on a large number of crash, roadway, and traffic variables. It uses data already being collected by States for managing the highway system and studying highway safety. The data are acquired annually from a select group of States, processed into a common computer format, documented, and prepared for analysis. Data are available to requestors in multiple formats including comma-separated values (.csv), Microsoft Excel, SAS, and GIS shape files.