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:
Royal_Institute_of_British_Architects

Context:
Soon after the passing of the 1931 Act, in the book published on the occasion of the Institute's centenary celebration in 1934, Harry Barnes, FRIBA, Chairman of the Registration Committee, mentioned that ARCUK could not be a rival of any architectural association, least of all the RIBA, given the way ARCUK was constituted. Barnes commented that the Act's purpose was not protecting the architectural profession, and that the legitimate interests of the profession were best served by the (then) architectural associations in which some 80 per cent of those practising architecture were to be found.

Question:
In 1934, what percentage of architects were members of professional organizations?

80 per cent