IO_CELL_OFFLOAD_RETURNED_BYTES stats

I am check a query statistics in Exadata and I noticed that v$sql.IO_CELL_OFFLOAD_ELIGIBLE_BYTES is cero but IO_CELL_OFFLOAD_RETURNED_BYTES has a pretty high value.

How can this possible?

*selectexecutions,disk_reads*16384/(1024*1024)
PHY_MB,IO_CELL_OFFLOAD_ELIGIBLE_BYTES/1024/1024 as "OFFLOADED_MB", IO_CELL_OFFLOAD_RETURNED_BYTES/1024/1024 as "OFFLOAD_RT_MB",IO_INTERCONNECT_BYTES/1024/1024 as

"ICONNECT_MB",PHYSICAL_READ_REQUESTS      ,PHYSICAL_READ_BYTES/1024/1024
PHY_R_MB         , PHYSICAL_WRITE_REQUESTS
,PHYSICAL_WRITE_BYTES/1024/1024 PHY_W_MBfrom v$sqlwhere sql_id =
'4j92kqhrpcpr6'EXECUTIONS     PHY_MB OFFLOADED_MB OFFLOAD_RT_MB ICONNECT_MB

---------- ---------- ------------ ------------- -----------
---------------------- ---------- -----------------------
----------         1 130755.328            0    259544.156
520041.828                2801860 130598.375                  641580

*Thanks*

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