Specifications include, but are not limited to: Task 1: Literature Review and Data Collection The Contractor will collect, review and synthesize scientific, technical and trade literature offering insights into the factors that predict medium- and heavy-duty truck fleet turnover, as well as interstate and international migration of fleet trucks to and from California. The review will cover: truck fleet business models and turnover modeling; replacement cycles and rationales; scrappage; truck migration; regulatory compliance requirements, economic lifecycle analysis of trucks; related taxation policies and financial practices; and business cycle impacts. The Contractor will also evaluate and summarize the results of surveys relevant to these subjects. Task 2: Structured Interviews with Industry Sources Contractor shall conduct structured interviews by telephone and/or in person to gather insider knowledge of truck fleet business models, turnover practices and related decision-making factors. Interview results will elucidate how private fleet operators decide what vehicles to acquire and dispose of, and when to buy, sell or scrap them. Interviewers will ascertain to whom fleet vehicles are sold, and how and where are they subsequently used. Task 3: Fleet Turnover Data Analyses Contractor will analyze representative samples of truck ownership and registration data to quantify and characterize patterns of vehicle acquisition and disposal for selected fleet and vehicle types during the period 2000-2017. The analysis will identify the attributes of acquired, scrapped and sold vehicles for selected fleets, and will support development of vehicle lifetime ownership/use/cost-effectiveness profiles. Other data, such as those contained in corporate financial data sets will be analyzed to categorize vehicles and vehicle owners by industry sector and to identify, quantify and segment businesses that operate (or operated) medium- and heavy-duty truck fleets in California.