Bucharest Stock Exchange. The Stock Exchange is for the people! - details Shares CICO CI-CO SA

To ensure a share price chart shows an accurate reflection of the share price, the graph may be 'rebased' to take into account corporate actions that affect the price, but not the value. For example, companies may consolidate their shares in a 2 to 1 consolidation. For the investor, on the effective date of the consolidation, the volume of shares held in that company may half, but the value of the shares would double, leaving the holding value unchanged. However, an unbased chart would show a sudden jump in the share price. Rebasing smooths out the chart to provide a view of the share price performance unaffected by the technical changes caused by corporate actions.

Note:
The price evolution charts are rebased for all corporate actions that trigger a change in their market price (e.g. bonus shares, split, reverse split, etc.).