Ha :  Proportion of people riding bikes after January (during the month of February)is less than that of January.                                                                         
Proportion of people (riding in January)   <  Proportion of people (riding in February)

The data used was the months of January and February for the year 2016 and 2017 and the test used was the Z test for proportions.
We performed the Z test for proportions to test our hypothesis, as suggested by Devashish. We obtained a p-value of 0.0016, thereby rejecting the null hypothesis that there is no difference in the proportion of ridership between the month of January and February