On grounds of the Network Code, the Transmission System Operator as of 3 July 2013 applies such balancing energy ratios:

1. Balancing energy selling price for service providers is set by multiplying the balancing energy price by ratio 1.03;
2. Balancing energy purchase price for service providers is set by multiplying the balancing energy price by ratio 0.97.

You can find the new edition of the Network code here.

You can find the methodology for balancing energy here.