The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
Premiere date confirmed on the title's own MyAnimeList listing.
Lists SPECIAL-1 'Prologue' (28 Dec 1992) with its nine segment titles and later specials through 1998 with air dates.[1]
TV Asahi premiere 13 April 1992, shift to original stories mostly in specials, export to over 85 countries.[1]
Wikipedia's[2][3] article on the franchise confirms Yoshito Usui's manga as the source[1] and its Kasukabe setting.
Something missing or wrong? Say it in your own words: a link that backs this pin up, a different start or end date and why, or a fact it lacks or gets wrong. The AI checks it against this pin's sources, searches for better ones, and adds any page that backs you up. The pin's own sources still count most. A picture that shows something else, or shows it badly, is looked at too, and moved down or replaced.