How to reduce the quantity of old item lines in cost type Frozen

Hello,

I have a question about Oracle EBS R11.5.10.2 Cost Management - Cost type "Frozen" for an inventory org.

Current state:

> Cost Type Frozen contains 1 million unique item records who all have unit costs values;

   > Most of these item records (90%) have a total unit costs of 0.00 (zero);

   > We use standard costing;

   > The business (operations & finance) only use 5k (5000) unique item records, these are being costed (once per year) with values higher then 1;

Problem:

1) Running a report like "Item Cost Reports" gives me a big file with 1 million records (this is too much information);

2) Performing a "Update Standard Cost" program is taking multiple hours to complete; (in other words, the business colleagues performing year end costing, are worried and spend a lot of time waiting..)