Statistics concerning the number of deaf people are difficult to obtain for three main reasons.
The first reason is clearly indicated by laws regarding technology, files and freedoms
Chapter I Article 8: It is prohibited to collect or process personal data that reveals, directly or indirectly, a person’s racial or ethnic origins, political opinions, philosophies or religions or union membership, or that relates to their health or sex life.
The second reason is that there are different types of deafness–profound deafness, mild deafness–and therefore different groups of deaf people categorized by how they handle their deafness–the signing deaf, the oral deaf, deaf individuals with cochlear implants, etc.
Last but not least, the third reason is the ban on learning and using sign language as a means of communication in 1880 during the Milan Conference. For nearly 100 years, the deaf were forced to communicate orally. It was only due to rare occasions, thanks to deaf homes and certain athletic associations, that sign language was able to survive. In 2005, the law recognized sign language as a full blown language. Nowadays, there are 300,000 signing deaf people.