Disclosed are systems and methods for determining whether a user of a navigation software or service has left a parking space and hence the parking space may have a potentially free space. The described technique comprises receiving an indication of a transportation-behavior change at a location; identifying one or more candidate parking spaces based on the received indication of the transportation-behavior change; calculating, for each of the candidate parking spaces, a confidence level that a user has left a respective a respective candidate parking space; and finally, identifying, based on a maximal confidence level, an available parking space, the available parking space having been vacated by the user.