What are "MIB counters" in Ethernet?

In some Ethernet switch or router datasheets you see sentences like

Gathers 34 MIB counters per port MIB means Management Information Base, that is information that can be used to manage a networking system.

A typical set of MIB counters is:

These can be used to compute other parameters such as the current throughput. For example, to calculate the transmit throughput, use