what blocks are 90% empty and there is a back log?
Essentially all. None of the last 100 blocks were larger than 400KB. Only 5 were larger than 300KB. The vast majority are 100KB to 250KB. More than 20 are <100KB. The block size limit is 1MB.
why are miners creating a back log when they have plenty of space.
why not include all the TX's if there is space for them?