CST_STANDARD_COSTS

I want to create a report to get the Standard Cost for an Item. That Report needs to tell the History of an item over the time. I am think to use the above-mentioned table.

1. Is Standard Cost get updated manually or you need to run a process which can create a row in the above mentioned table.

2. In which circumstances above mentioned table is not going to get populated for the Standard Cost of an item.

Is there any other table more reliable to use.

Thanks