Energy Dashboard - Percentage used of Total consumption

As title says, total consumed should be 100%. It would be nice if sources would report % of total besides individual value in kWh.

For example
Source 1: 8kWh (80%)
Source 2: 2kWh (20%)
Total consumption: 10kWh (100%)

This is just for consumption. Any ideas how to apply this to energy production beside negative percentage?