 
<translate> Mee ka uche gị dịrị n'ihe ị na-ekwu tupu ị zaa ajụjụ ndị a. Passage: Alaeze Ukwu ahụ ruru ebe kachasị ukwuu n'okpuru Trajan (chịrị 98 - 117), na-ekpuchi mpaghara nke 5 nde square kilomita. Nkọwa ọnụ ọgụgụ ndị bi na ya bụ nde 55 ruo nde 60 bụ ihe dị n'agbata otu ụzọ n'ụzọ isii na otu ụzọ n'ụzọ anọ nke ọnụ ọgụgụ ndị bi n'ụwa dum ma mee ka ọ bụrụ ọnụ ọgụgụ kasị ukwuu nke ndị bi n'otu ọchịchị ọ bụla dị n'Ebe Ọdịda Anyanwụ Ụwa ruo n'etiti narị afọ nke 19. Nnyocha ndị e mere n'oge na-adịbeghị anya na-egosi na ọnụ ọgụgụ kasị elu nke ndị bi n'ụwa ga-eru site na nde 70 ruo ihe karịrị nde 100. Nke ọ bụla n'ime obodo atọ ndị kasị ibu n'Alaeze Ukwu ahụ - Rom, Aleksandria, na Antiọk - ji ihe fọrọ nke nta ka o jiri okpukpu abụọ karịa obodo ọ bụla ọzọ dị na Europe ná mmalite narị afọ nke 17.  Ajụjụ: Olee mgbe Alaeze Ukwu Rom dị n'ike n'ihi ihe e kwuru n'amaokwu a? <eng> Output a stream of consciousness before answering the following. Passage: The Empire reached its largest expanse under Trajan (reigned 98 -- 117), encompassing an area of 5 million square kilometres. The traditional population estimate of 55 -- 60 million inhabitants accounted for between one-sixth and one-fourth of the world's total population and made it the largest population of any unified political entity in the West until the mid-19th century. Recent demographic studies have argued for a population peak ranging from 70 million to more than 100 million. Each of the three largest cities in the Empire -- Rome, Alexandria, and Antioch -- was almost twice the size of any European city at the beginning of the 17th century.

Question: Based on this passage, when was the roman empire at its peak? 