User blog comment:Henshin1971/The Showa counterpart of Ultimate Force Zero's member/@comment-1060835-20130831052349/@comment-4793248-20130831054921

Now I know why it called Jumborg 9. This is my opinion about his name:

1. 1966 - Ultra Q & Ultraman

2. 1967 - Ultraseven

3. 1968 - Mighty Jack

4. 1969 -

5. 1970 -

6. 1971 - The Return of Ultraman (Ultraman Jack) & Mirrorman

7. 1972 - Redman & Ultraman Ace

8. 1973 - Fireman, Jumborg Ace, Ultraman Taro

Sorry if not complete but I watch this video before comment:https://www.youtube.com/watch?v=YeeSI5axXfM

It based on year which Tsuburaya has made their own heroes series. I guess lol