 The <unk> of Yue <unk> lists the events at Zhou 's tomb happening in 1121 when Yue was nineteen , but Yue would have been eighteen in that year since he was born on " the fifteenth day of the second month of 1103 " . The author of the original source material was using <unk> age calculation , in which a child is already considered one year old at birth . Since Yue joined the military shortly after Zhou 's death , a relative time frame can be given for when he died . During the early months of 1122 , the Song empire mobilized its armed forces to assist the Jurchen in <unk> their common enemy , the Liao Dynasty . Therefore , it appears that Zhou died in late 1121 , before the call to arms was issued . 
