The perfect bike to participant, bike share ratio?

[Robinson Eaton]

Hi. I'm new to this forum, but not to bike sharing. For the past 6 months, I've been working as a project manager for the Open Bike initiative, an ad hoc project based out of Intel's Oregon campuses, focused on developing, piloting and disseminating open source bike share technology. Throughout the past few months, we've made some great strides on an open source platform I think you all will enjoy. As of now, that platform and the associated technology is still in the development phase, but I hope we will have something to show you soon, but that is for another day and another topic. 

Today, I am writing to ask whether any of you brilliant bike share advocates feels they have stumbled upon the right bike to participant ratio for bike share? For our pilot we used a .1 ratio, which worked quite well, but probably would not be scalable for larger corporate and university campuses. I am in the process of attempting to define the market potential for university and corporate campus bike share programs and feel a good baseline ratio is fundamental to making realistic projections. If anybody here has any recommendations or links they think would be helpful, I'd sincerely appreciate it. 

Thanks,

Rob Eaton 

[Sean Bailey]

I think what you should be looking for instead of bike-participant ratio is ride/bike/day.  I've heard (although I can't cite where) that you generally want each bike to be ridden 3-5 times per day.  Your participant number will probably fluctuate as you get "regular" users and "casual" users and you don't want to have to go adding bikes to your system or taking them out as the number of members changes.  In Boston, it's not unusual for us to have 2-3 thousand people sign up for just the day, only to ride while they are in town.  I don't know how that would translate to a University Campus.  Hypothetically, even if students and faculty all received a free membership with their affiliation, some would never ride while others would be rabid about riding.

Hope that helps.

[Cyrille Médard de Chardon]

As far as I know there exists nothing like this (subscribers:bikes ratio) in the literature. There is unlikely to be one ideal ratio. The ratio will depend heavily on the network structure and relative spatial and temporal flows, whether it's uniformly central (~Paris/London core) or decentralized and turbulent (University campus). In the former bikes will get fewer uses and you will want/need a higher ratio of bikes to users to keep subscriber satisfaction up. Keep in mind that most bike share systems haven't reached equilibrium, many are still expanding so it may be too early to extract a golden ratio.

As Sean said perhaps you could look at other variables more commonly used in the literature. Sean also mentioned this issue with short term subscriptions. The ratio of yearly and short-term subscribers may therefore be of interest to you as well.

That's it from me.

Cheers,

Cyrille