Performance

A measure of the efficiency of a stake pool, given as a percentage, is measured by how many blocks the stake pool has produced (and that are recorded on the main chain) compared to how many it was nominated to produce. For example, if a pool only produces half the number of blocks that were nominated, its performance rating is 50%. This could happen because the pool has a poor network connection, or has been turned off by its operator. Performance ratings make more sense over a longer period of time.