WIG-energy is a sub-sector index and its portfolio includes WIG constituents belonging to the ‘energy’ sector. Weightings in the index are the same as in the WIG index portfolio. WIG-energy index base date is December 31, 2009. The initial value was 3988.60 points. It is an income-based index and thus when it is calculated it accounts for both prices of underlying shares and dividend and pre-emptive rights‟ income.