In what year was Eurovision Song Contest song number 100 performed?

Explanation

More than 1.300 songs already have taken part in the Eurovision Song Contest. During the Eurovision Song Contest 2006 Ireland's Brian Kennedy contributed with "Every Song Is a Cry for Love" which was ESC song number 1.000. In 2003, Cyprus delivered song number 900 when Stelios Konstantas sung "Feeling Alive". In 1999, Lydia's "No Quiero Escuchar" was the 800th song. Song number 100 was "T'en Va Pas", performed by Esther Ofarim for Switzerland.