A computer-implemented method comprising: receiving a plurality of sensor quality communications, each sensor quality communication comprising a location, a timestamp, and a sensor quality metric; partitioning the sensor quality metrics of each of the plurality of sensor quality communications into groups based on the corresponding location and timestamp; for at least one group of the groups, determining a sensor quality index based on the corresponding sensor quality metrics; associating the sensor quality index with (a) a traversable map element, TME, based on the corresponding locations and (b) an epoch based on the corresponding timestamps; generating or updating a sensor quality index table based at least in part on the sensor quality index and the corresponding traversable map element and epoch; and providing the sensor quality index table to at least one vehicle apparatus for use in performing at least one navigation function, characterized in that determining the sensor quality index comprises: determining a sensor quality metric distribution for at least one group, the at least one group corresponding to a first TME and first epoch; determining whether the sensor quality metric distribution is unimodal; responsive to determining that the sensor quality metric distribution is unimodal, determining a sensor quality index corresponding to an entire length of the first TME; and responsive to determining that the sensor quality metric distribution is not unimodal: determining one or more offset points along the first TME that define two or more sub-TMEs, each sub-TME corresponding to a unimodal sensor quality metric distribution, and determining a sensor quality index corresponding to each sub-TME, wherein the sensor quality index table is generated or updated to include the sensor quality index corresponding to each sub-TME for the first epoch. receiving a plurality of sensor quality communications, each sensor quality communication comprising a location, a timestamp, and a sensor quality metric; partitioning the sensor quality metrics of each of the plurality of sensor quality communications into groups based on the corresponding location and timestamp; for at least one group of the groups, determining a sensor quality index based on the corresponding sensor quality metrics; associating the sensor quality index with (a) a traversable map element, TME, based on the corresponding locations and (b) an epoch based on the corresponding timestamps; generating or updating a sensor quality index table based at least in part on the sensor quality index and the corresponding traversable map element and epoch; and providing the sensor quality index table to at least one vehicle apparatus for use in performing at least one navigation function, characterized in that determining the sensor quality index comprises: determining a sensor quality metric distribution for at least one group, the at least one group corresponding to a first TME and first epoch; determining whether the sensor quality metric distribution is unimodal; responsive to determining that the sensor quality metric distribution is unimodal, determining a sensor quality index corresponding to an entire length of the first TME; and responsive to determining that the sensor quality metric distribution is not unimodal: determining one or more offset points along the first TME that define two or more sub-TMEs, each sub-TME corresponding to a unimodal sensor quality metric distribution, and determining a sensor quality index corresponding to each sub-TME, wherein the sensor quality index table is generated or updated to include the sensor quality index corresponding to each sub-TME for the first epoch. determining a sensor quality metric distribution for at least one group, the at least one group corresponding to a first TME and first epoch; determining whether the sensor quality metric distribution is unimodal; responsive to determining that the sensor quality metric distribution is unimodal, determining a sensor quality index corresponding to an entire length of the first TME; and responsive to determining that the sensor quality metric distribution is not unimodal: determining one or more offset points along the first TME that define two or more sub-TMEs, each sub-TME corresponding to a unimodal sensor quality metric distribution, and determining a sensor quality index corresponding to each sub-TME, wherein the sensor quality index table is generated or updated to include the sensor quality index corresponding to each sub-TME for the first epoch. determining one or more offset points along the first TME that define two or more sub-TMEs, each sub-TME corresponding to a unimodal sensor quality metric distribution, and determining a sensor quality index corresponding to each sub-TME, wherein the sensor quality index table is generated or updated to include the sensor quality index corresponding to each sub-TME for the first epoch.