The shows are grouped together in order to keep the chart compact.
The shows' horizontal placements are based on original airdates, but does not take into account competition within the same timeslot during Voyager's original airdate, or reruns of other shows elsewhere.
Preference is for continuous series; separate movies, tv-movies and miniseries are not included, unless a continuous miniseries was aired during Voyager's run.
"The Outer Limits" was often Earth-based, but variably featured space-based stories.
The last episode of "Sliders" aired on 4 February 2000 in the U.S.; in the UK, it did on 29 December 1999.
I've avoided some of the following: kids' shows, such as Young Hercules, which is a spin-off of Hercules; sci-fi/fantasy comedies and cartoons (Futurama's original run being the sole exception), and relatively weak shows, such as The Immortal (a blatant rip-off of Highlander).
It should be noted, though, that Voyager—family-friendly as it was—did actually compete with many of the kids' shows (that I had decided to keep out), and the teen-oriented series, of which some are in the chart.
