It is possible to display the time elapsed (parameter ETD in AMSO SDAT) instead of the call charges (parameter CDRSTN in AMO COSSU) at the station terminal during incoming or outgoing trunk calls. While CDRSTN is set up through the COS, ETD is set up on a per-subscriber basis with ETD taking priority over CDRSTN. This means that if both parameters are configured, the display shows the time elapsed and not the call charges recorded.