Rome's population declined after its peak in the 2nd century. At the end of that century, during the reign of Marcus Aurelius, the Antonine Plague killed 2,000 people a day. Marcus Aurelius died in 180, his reign being the last of the Five Good Emperors and Pax Romana. His son Commodus, who had been co-emperor since AD 177, assumed full imperial power, which is most generally associated with the gradual decline of the Western Roman Empire. Rome's population was only a fraction of its peak when the Aurelian Wall was completed in the year 273 (in that year its population was only around 500,000). At this time, part of the Roman aristocratic class circulated in Rome following the catastrophic eruption of Mount Vesuvius in 79 AD, which destroyed the city of Pompeii.