What do you do when you are one of the biggest indices in Europe and are unable to rise simply because two of your biggest constituents, if not so much in market cap any more but certainly in terms of systemic importance, just can't catch a bid? Why you delete them, of course even if the two names in question happen to be Europe's two largest banks, Deutsche Bank and Credit Suisse.

Moments ago, STOXX Ltd, the operator of Deutsche Boerse Group’s index business, announced component changes in the STOXX Europe 50 Index due to the fast-exit rule. All changes become effective with the open of markets on Aug. 8, 2016.

What is the Fast Exit rule? "The rule states that a component is deleted from the Dow Jones EURO STOXX 50 or Dow Jones STOXX 50 indexes if it ranks 75 or below on the respective index's monthly selection lists for a consecutive period of two months. Deleted components for all three indexes will be replaced by the highest ranking non-components on the monthly selection list. Component changes will be announced on the first trading day of the month following the publication of the monthly selection lists, implemented on the close of the fifth trading day and effective the next trading day."

In other words, someone did not like how DB and CS were trading and decided to kick them out.

And here are the replacements.

What does this really mean from a price index standpoint? Simple: the following.

And that is how you "boost" the performance of the constituent index. It was not immediately clear if there would be any forced selling as a result of these names getting kicked out of one of Europe's 2 most important indices alongside the broader Stoxx 600 index.