Our measure of % Complexity for all 10-K filings 1996-2021. The measure is developed in Measuring Firm Complexity (Loughran/McDonald), which is forthcoming in JFQA. The lexicon is free for use in academic research. For commercial licenses, please contact us at

Loughran_McDonald_Complexity.csv - cik, filingdate, complexity, log_netfilesize

Loughran_McDonald_ComplexityLexicon.xlsx - complexity word list


Measuring Firm Complexity


In business research, firm size is both ubiquitous and readily measured. Complexity, another firm-related construct, is also relevant, but difficult to measure and not well defined. As a result, complexity is less frequently incorporated in empirical designs. We argue that most extant measures of complexity are one-dimensional, have limited availability, and/or are frequently misspecified. Using both machine learning and an application-specific lexicon, we develop a text solution that uses widely available data and provides an omnibus measure of complexity. Our proposed measure, used in tandem with 10‑K file size, provides a useful proxy that dominates traditional measures.