From the Methodology: "The 2021 Menino Survey of Mayors uses a combination of open- and closed-ended questions to explore salient local issues including COVID-19 [coronavirus disease 2019] recovery, equity and small business, closing the racial wealth gap, and housing and homelessness. Within these areas it assesses, among other things, mayors' beliefs and priorities. This year, the data comprises responses from 126 mayors. [...] The Menino Survey relies on a systematic sample in which all US mayors who lead cities with at least 75,000 residents are invited to participate. Each received an email invitation from the Boston University Menino Survey of Mayors team at their official email account, and follow-up phone calls. The vast majority of interviews were conducted over the phone. Mayors' responses and participation remain anonymous, in order to ensure they are able to speak freely about a wide range of issues. In 2021, this sampling and recruitment effort yielded a sample that was representative of the full set of US cities with at least 75,000 residents." This document includes charts, tables, and graphs to illustrate the text.
Boston University. Initiative on Cities
Rockefeller Foundation: https://www.rockefellerfoundation.org/