You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
European_Union_law

Context:
Proportionality is recognised one of the general principles of European Union law by the European Court of Justice since the 1950s. According to the general principle of proportionality the lawfulness of an action depends on whether it was appropriate and necessary to achieve the objectives legitimately pursued. When there is a choice between several appropriate measures the least onerous must be adopted, and any disadvantage caused must not be disproportionate to the aims pursued. The principle of proportionality is also recognised in Article 5 of the EC Treaty, stating that "any action by the Community shall not go beyond what is necessary to achieve the objectives of this Treaty".

Question:
How long has Proportionality been recognized as one of the general principles of EU law?

since the 1950s