Being able to evaluate the quality of grammars in Grammar Engineering is very important, as it is in all software fields. This allows us to verify the grammar's behaviour regarding the purpose that it was designed to. On the other hand, it serves as an indicator to compare differents grammars. Quality can be assessed by the quantification of a subset of software metrics relying on static analysis. In most author's opinion, quantification is a powerful and essential tool. With it we can understand and control the grammar evolution which will improve some aspects such as performance and reliability. Measuring metrics is an old and well used habit in software systems for all those you cares about it maintenance because is related to the quality of the source code system. This effort has been short when applied to the maintenance of grammar-based software applications. Just few authors mentioned software metrics to evaluate grammars, so it is motivating to select and implement a set of metrics to be possible to assess and discuss grammars quality. You cannot control what you cannot measure. DeMarco, 1982.