Introduction - CitiBike is New York City's bikeshare system. Such a system allows users to rent bicycles for a short amount of time, picking them up from one station and depositing them at an end destination station. Bikeshare systems have become more and more popular across the globe in major world cities as it allows a cheap, sustainable, and healthy alternative for transportation. However, for the system to be truly effective, it must reach all segments of the population. Thus, it is prudent to know which segments of the population the system is currently or is not currently serving. Our thesis is that because of the nature of cycling as a physical activity, those with lesser physical abilities will use the system less. If we hold the hypothesis that as one ages, one's physical abilities decline, then we would expect to see that the system is heavily biased towards younger riders. That is, we hypothesize that the proportion of system users that are "young" greatly outweighs the proportion of users that are "old". It is important now to define what we mean by old or young. We use a study from the Journal on Gerontology which finds that a person's physical abilities begin to decline in their 50s. Thus we will use 50 as a cutting off point, creating a binary category in the data for young or not. 
If we find this hypothesis to be true, this gives impetus to the argument that the system should perhaps have an electrified component giving riders with diminished physical abilities a boost up and opening the system up to them to use as well, not just the young and healthy. Urban transportation is not just about efficacy but also equity. What use is a system if it does not serve the entire population equitably? We ensure that our subway stations have elevators as part of compliance with the Americans with Disabilities Act. It is of course true that to use a cycling system, one must have a baseline level of physical abilities and it would be nonsense to get rid of the entire system because it does not meet the needs of those with more severe mobility challenges. But it is nevertheless important to try to open the system up to as many people as possible by identifying the challenges that they currently face. By investigating any difference in the age of users and by hypothesizing a link to physical abilities attached to age, we can perhaps identify one of these challenges and perhaps a way to remove this barrier.