In less than a decade, public bike-sharing programs (PBSPs) have spread from being sited in a handful of European cities to now include five continents and more than 486 urban areas. Public bicycle docking stations, which prior to 2008 did not exist in Asia, Australia, and the Americas, are now a recognizable fixture in many of their urban landscapes. The goals of individual PBSPs vary, but most aim to provide more mobility choices, reduce vehicle emissions, reduce congestion, or increase the status of cycling (Midgley, 2011). Figure 1 documents the rapid rise of large-scale PBSPs, defined here as programs with a minimum of 100 bicycles and 10 docking stations. Included in this count are 200 PBSPs, of which 139 or 70 per cent were initiated in 2010, 2011, or 2012.
In light of the rapid rise of PBSPs, the academic literature is sparse, and as such numerous research gaps persist. These include impacts of policies on PBSPs, holistic analysis of their costs and benefits as well as the interface between land use and PBSPs, among others. To help redress this limited research, this paper present s a series of metrics that have the capacity to explore and profile PBSPs drawing on routinely collected usage data. Here we focus on two PBSPs, Washington, D.C.’s Capital Bikeshare and Brisbane CityCycle. These two programs are regarded suitable candidates for analysis given that the programs are of a similar size and began within weeks of each other. However, the two cities differ significantly in both planning and policy contexts (e.g. population density, climate, topography, station density, modal split, and on-street bicycle infrastructure), therefore this paper does not compare performance; rather, we analyse the trends and speculate on underlying causes of these trends. The focus of the analysis and discussion will centre on the temporal and spatial dynamics during their first 18 months of operation. The discussion will suggest possible causes of the fluctuations in ridership over monthly, weekly, and daily time periods. The discussion additionally explains neighbourhood performance trends are not uniform across the entire system. The analysis endeavours to inform the practice of what the expectations for ridership should be in more car-dependent cities.
The remainder of the paper is structured as follows: in the next section we provide an overview of the PBSP literature in which we acknowledge the major research needs. In the following section, we provide some background information about Capital Bikeshare and Brisbane CityCycle, as well as a description of the materials and methods that were used in the research. The fourth section contains an analysis of the spatial and temporal trends of each program. The final section provides a discussion of their trends, the limitations of the analysis, and areas for future research.