Download the Data
Below are the data sets used for the creation of the Legislative Effectiveness Scores (LES) and Issue Area Data. For more information about how these are constructed, go to our FAQ and Methodology pages.
All House data from 93rd-118th Congress (1973-2024) (including both LES 1.0 and 2.0).
All Senate data from 93rd-118th Congress (1973-2024) (including both LES 1.0 and 2.0).
Issue Area Data for 93rd-118th Congress (1973-2024) (Classic methodology)
State Legislative Effectiveness Scores (through 2018)
These are the data that served as the foundation for the analysis in
Legislative Effectiveness in the American States.
State Legislative Effectiveness Scores (through 2025)
These data include State Legislative Effectiveness Scores for all state legislatures that completed their legislative sessions through 2025. These data will be periodically updated in the year immediately following each state legislature’s general election.
Codebook
How to cite these data:
For House data: Volden, Craig, and Alan E. Wiseman. 2014. Legislative Effectiveness in the United States Congress: The Lawmakers. New York: Cambridge University Press; updated at www.thelawmakers.org.
For Senate data: Volden, Craig, and Alan E. Wiseman. 2018. “Legislative Effectiveness in the United States Senate,” Journal of Politics 80(2): 731-735; updated at www.thelawmakers.org.
For States data used in the 2025 American Political Science Review article: Bucchianeri, Peter, Craig Volden, and Alan E. Wiseman. 2025. “Legislative Effectiveness in the American States,” American Political Science Review 119(1): 21–39; updated at www.thelawmakers.org.
For updated States Data (through 2025): Bucchianeri, Peter, Craig Volden, and Alan E. Wiseman. 2026. “State Legislative Effectiveness Scores Dataset”; updated at www.thelawmakers.org.”
