Once a station records up to 56 hours of Downtime for the week they are temporarily removed from their reporting panel(s). Downtime is defined as at least 45 minutes during which BDS is unable to accurately monitor a radio station, network or channel. Some causes of Downtime include:
- hardware crash or power outage at BDS monitor site
- loss of communication with BDS monitor
- station transmitter issues
- station stream is down (where applicable)
- reception issue for station
Note that Downtime impacts less than 1% of the total minutes monitored by BDS. If Downtime for a station exceeds 56 hours within a Mon-Sun chart week the station will be temporarily removed from the Billboard chart panels. Once the issue is resolved and there are two full weeks of
good detection data available the station will be returned to the charts. This is necessary so that there is complete "This Week" and "Last Week" data for the chart. This policy eliminates unnatural fluctuations in airplay due to additions and removals of stations.
Billboard factors all Downtime into their bullet criteria for the charts. For example if total Mon-Sun Downtime for a particular airplay format equals 3% of the total monitored minutes during the week (number of stations times minutes in the week) then the +/- number for all songs on the chart will be
adjusted by 3% for bullet calculations. So a song could have a negative gain in spins or audience but still retain its bullet.
If the cause of the Downtime was loss of communication with the BDS monitor, those detects will be filled in once that internet connection is restored. This is due to the monitor itself being up-and-running during the Downtime period. If those detects fill in after a chart has closed, they will not be included in the charts but will be included in song-level and station-level data.