https://esg.wharton.upenn.edu/zicklin-center/zicklin-bright-index/
https://www.nber.org/system/files/working_papers/w30028/w30028.pdf
https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef1663en.pdf
https://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.38.3.89