Index conditional aggregate query on PostgreSQL
You'll have to create a special table to contain the sum.

Then create triggers on the original table that add values that are inserted, subtract values that are deleted, do both for an update and set the value to zero on truncate.

You can see a small example of that for the count aggregate in my blog post. Different from that example you will have to have a summation table with one sum per "PlayerId" and status.