nload is described as 'Console application which monitors network traffic and bandwidth usage in real time. It visualizes the in- and outgoing traffic using two graphs and provides additional info like total amount of transfered data and min/max network usage' and is a Network Monitor in the network & admin category. There are more than 10 alternatives to nload for a variety of platforms, including Linux, BSD, Mac, Windows and Go (Programming Language) apps. The best nload alternative is Munin, which is both free and Open Source. Other great apps like nload are Nethogs, iftop, Cacti and ntop.
It could monitor and show your server network traffic stats monthly.