Calculating pga_aggregate_target using v$pga_target_advice but values of ESTD_PGA_CACHE_HIT_PERCENTA

Hi,

I am running the following query in a database 11.2.0.3.0

SELECT round(PGA_TARGET_FOR_ESTIMATE/1024/1024) target_mb,

      ESTD_PGA_CACHE_HIT_PERCENTAGE cache_hit_perc,

      ESTD_OVERALLOC_COUNT

FROM v$pga_target_advice;

TARGET_MB CACHE_HIT_PERC ESTD_OVERALLOC_COUNT

---------- -------------- --------------------

       320              0                   13

       640              0                    0

      1280              0                    0

      1920              0                    0

      2560              0                    0

      3072              0                    0

      3584              0                    0

      4096              0                    0

      4608              0                    0

      5120              0                    0

      7680              0                    0

     10240              0                    0

     15360              0                    0

     20480              0                    0

But values for ESTD_PGA_CACHE_HIT_PERCENTAGE and ESTD_OVERALLOC_COUNT are mainly 0:

Do you know the reason? ….. I know I have problems with PGA because “Undersized PGA” is one of the findings in ADDM Report but I cannot calculate the value based on v$pga_target_advice

Values for memory and statistics are setting like this: