Year range Goober and the Ghost Chasers

Currently, Goober and the Ghost Chasers has a year range of 1973-1975: https://www.imdb.com/title/tt0157227/reference/ 

However, as you can see, all episodes on IMDb are from 1973.

TMDB also says this series only ran in 1973: https://www.themoviedb.org/tv/12396-goober-and-the-ghost-chasers 

So does epguides.com: https://epguides.com/GooberandtheGhostChasers/ 

Can a staffer look into this and fix the year range please?