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README.md

@@ -8,7 +8,7 @@ Zebus is **peer to peer**, so it does not depend on a broker to dispatch message
 
 It is **resilient** thanks to the absence of a broker and an optional persistence feature that ensures that messages are not lost if a peer is down or disconnected.
 
-It is **stable**, since we have been using it on a production environment at [Abc Arbitrage](http://www.abc-arbitrage.com/) for more than two years. Although we did not release all the necessary bricks yet so you will have to wait a few minor versions to have a fully resilient prodable product.
+It is **stable**, since we have been using it on a production environment at [Abc Arbitrage](http://www.abc-arbitrage.com/) for more than four years. Although we did not release all the necessary bricks yet so you will have to wait a few minor versions to have a fully resilient prodable product.
 
 ## Key concepts