st04 oracle table statistics missing

Hi expert,

  Our oracle database upgrade from 11.2.0.3 to 11.2.0.4, then I find lots of oracle  tables statisticses missing

Then I update statistic with program rsanaora. But the system issue the same problem in st04 and I cannot see the talbe statistics. But I check the Execution Plan with ST05, then I can see the table statistics below:

But the Execution Plan is still TABLE ACCESS FULL COBRB. But the Execution Plan is executed with index COBRB~1 before the oracle database upgrade below:

SELECT STATEMENT ( Estimated Costs = 46,801 , Estimated #Rows = 479,147 )

       2 TABLE ACCESS BY INDEX ROWID COBRB
         ( Estim. Costs = 46,801 , Estim. #Rows = 479,147 )
         Estim. CPU-Costs = 861,454,494 Estim. IO-Costs = 46,777
         Filter Predicates

           1 INDEX RANGE SCAN COBRB~1
             ( Estim. Costs = 1,714 , Estim. #Rows = 479,147 )
             Search Columns: 2
             Estim. CPU-Costs = 110,024,584 Estim. IO-Costs = 1,711
             Access Predicates

Can any expert help me ? Thanks  l lot.