This year the results of a very large survey about fear of public speaking was published in Asia-Pacific Psychiatry magazine. That article by T. A. Furukawa et al was titled Public speaking fears and their correlates among 17,615 Japanese adolescents and appeared in Volume 6 on pages 99 to 104. In 2008 and 2009 they surveyed a sample of adolescents both in junior (grades 7 to 9, ages 12 to 15) and senior (grades 10 to 12, ages 15 to 18) high schools. Students were in both in Kochi Prefecture and Mie Prefecture (in its capital, Tsu City). You can read the abstract here at PubMed, or download a pdf of the full text here.
Students were asked:
“Have you had trembling hands, quavering voice or lost voice due to tension and anxiety when speaking in front of other people in the past month?”
They could answer No, Probably No, Probably Yes, or Yes. Only the last Yes answers were taken as a positive result.
An overall average of 7.3% reported public speaking fear. Detailed results from their Table 1 are shown above by age in a bar chart. The percentages ranged from 5.7% to 9.1%, and tended to decrease with increasing age.
Results for both females and males by age are shown above in another bar chart. At all ages females reported higher percentages that feared public speaking than males did.
These percentages are similar to the 6.8% of Swedish adolescents in junior high school that reported a marked fear of speaking in front of the class.
These percentages are much lower than those reported for American adolescents in the NCS-A by Green et al ( 35.8% for Performing for an audience, and 24.9% for Speaking in class), but are not really comparable since the NCS-A asked for lifetime prevalence (Have you ever?) rather than monthly prevalence.