What was nerva greatest accomplishments

Nerva, or Marcus Cocceius Nerva Caesar Augustus was most known for being Roman Emperor from 96 to 98 AD. His reign was short lived and he had a hard time maintaining his authority over the Roman army. However, he saw that storehouses were built for grain. He swore that he would not execute any senators, and "pardoned" senator Calpurnius Crassus even after he was found guilty of conspiracy against Nerva. He put in place tax exemptions for inheritance, so land was able to be distributed to the poor, and he even used his own wealth to help fund it.