The output numerical value of {HEAD ~ differential production} is added to the current production rate of the plants to obtain a new production rate which is applied during {TAIL ~ the forecast period} 
The output numerical value of { HEAD ~ differential production } is added to the current production rate of the plants to obtain a new production rate which is applied during { TAIL ~ the forecast period }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL