Average Available PDSCH Resources

Hi Everyone.
Why is it that from OSS counters we always see Average Available PDSCH Resources counted as 2 less than the total available PRBs based on available BW?
For instance, for 20 Mhz instead of the counter showing 100 PRBs it reflects 98 PRBs.
Any insight on this please.

no idea must be a vendor limitation

PDCCH has fixed symbols assigned in time domain so not always they occupy the BW.

Yes, true, you’re right. Sorry, my mistake.