The demography of France is monitored by the Institut national d'études démographiques (INED) and the Institut National de la Statistique et des Études Économiques (INSEE). On 1 January 2011, 65,821,885 people lived in the French Republic. 63,136,180 of these lived in metropolitan France, whereas 2,685,705 lived in the French overseas departments and territories.
France was historically the largest nation of Europe. During the Middle Ages, more than one quarter of Europe's total population was French; during the 17th century, it was still one fifth of Europe's total population. At the beginning of the 20th century, France's population was low compared with that of its neighbors and with its previous history. However, the country's population sharply increased with the baby boom following World War II.
The national birth rate, after continuing to drop for a time, began to rebound in the 1990s and currently the country's fertility rate is close to the replacement level. According to an INSEE 2006 study, "The natural increase is close to 300,000 persons, a level that has not been reached in more than thirty years." Among the 802,000 newborns in metropolitan France in 2010, 80.1% had two French parents, 13.3% had one French parent, and 6.6% had two foreign-born parents.
A megaphone, speaking-trumpet, bullhorn, blowhorn, or loud hailer is a portable, usually hand-held, cone-shaped acoustic horn used to amplify a person’s voice or other sounds and direct it in a given direction. The sound is introduced into the narrow end of the megaphone, by holding it up to the face and speaking into it, and the sound waves radiate out the wide end. The megaphone increases the volume of sound by increasing the acoustic impedance seen by the vocal cords, matching the impedance of the vocal cords to the air, so that more sound power is radiated. It also serves to direct the sound waves in the direction the horn is pointing. It somewhat distorts the sound of the voice because the frequency response of the megaphone is greater at higher sound frequencies. Since the 1960s the voice-powered acoustic megaphone described above has been replaced by the electric megaphone, which uses electric power to amplify the voice.