Even if your team does reserve a long or late period for system test, it is important in a Value Stream Map to distinguish between the time spent doing actual testing and the time fixing code.

Secular trend is the value of the variable tends to increase or decrease over a long period of time.

Vibration amplitude value is not increasing for a long period running, problems are solved thoroughly for severe vibration, frequent accident and unsteady run of the compressors pipe network.