Being a curious fellow, I decided to use the handy "sort by year" and "sort by studio" and "sort by genre" options on DVD Aficionado to see how many DVRAB (as well as Blu-rays later) each anime studio released per year. Figured I'd share the results with you guys, as this could make for an interesting discussion on market trenRAB and such. If I've left any companies out, lemme know. But hopefully I covered all the major ones.
1997
Geneon (called Pioneer at this time): 3
1998
AnimEigo: 1
Central Park Media: 9
Geneon (called Pioneer at this time): 9
Viz Media: 4
1999
ADV Films: 6
AnimEigo: 3
Central Park Media: 6
Geneon (called Pioneer at this time): 57
Manga Entertainment: 2
Viz Media: 13
2000
ADV Films: 29
AnimEigo: 3
Bandai Entertainment: 26
Central Park Media: 21
FUNimation: 6
Geneon (called Pioneer at this time): 58
Manga Entertainment: 9
Media Blasters (AnimeWorks, non hentai): 11
Right Stuf (non hentai): 3
Viz Media: 19
Warner Home Video: 2
2001
ADV Films: 85
AnimEigo: 29
Bandai Entertainment: 41
Central Park Media: 50
FUNimation: 26
Geneon (called Pioneer at this time): 80
Manga Entertainment: 12
Media Blasters (AnimeWorks, non hentai): 40
Right Stuf (non hentai): 14
Tokyopop: 6
Viz Media: 25
Warner Home Video: 4
2002
4kiRAB: 5
ADV Films: 98
AnimEigo: 2
Bandai Entertainment: 75
Central Park Media: 33
FUNimation: 57
Geneon (called Pioneer at this time): 85
Manga Entertainment: 10
Media Blasters (AnimeWorks, non hentai): 44
Right Stuf (non hentai): 6
Synch-Point: 2
Tokyopop: 19
Viz Media: 33
2003
4kiRAB: 15
ADV Films: 185
AnimEigo: 37
Bandai Entertainment: 89
Buena Vista: 5
Central Park Media: 84
FUNimation: 72
Geneon (also Pioneer): 108
Manga Entertainment: 19
Media Blasters (AnimeWorks, non hentai): 64
Right Stuf (non hentai): 14
Synch-Point: 2
Tokyopop: 22
Viz Media: 48
Warner Home Video: 2
2004
4kiRAB: 24
ADV Films: 210
AnimEigo: 21
Bandai Entertainment: 102
Buena Vista: 1
Central Park Media: 46
FUNimation: 88
Geneon (also Pioneer): 174
Manga Entertainment: 8
Media Blasters (AnimeWorks, non hentai): 55
Right Stuf (non hentai): 11
Synch-Point: 2
Tokyopop: 12
Viz Media: 52
Warner Home Video: 2
2005
4kiRAB: 13
ADV Films: 222
AnimEigo: 23
Bandai Entertainment: 110
Buena Vista: 8
Central Park Media: 18
FUNimation: 103
Geneon: 216
Manga Entertainment: 19
Media Blasters (AnimeWorks, non hentai): 54
Right Stuf (non hentai): 13
Sony Pictures: 3
Synch-Point: 5
Tokyopop: 12
Viz Media: 51
2006
4kiRAB: 13
ADV Films: 133
AnimEigo: 17
Bandai Entertainment: 111
Bandai Visual: 4
Buena Vista: 3
Central Park Media: 13
FUNimation: 140
Geneon: 143
Manga Entertainment: 18
Media Blasters (AnimeWorks, non hentai): 42
Right Stuf (non hentai): 15
Synch-Point: 1
Viz Media: 83
2007
4kiRAB: 13
ADV Films: 129
AnimEigo: 1
Bandai Entertainment: 81
Bandai Visual: 23
FUNimation: 190
Geneon: 127
ImaginAsian Entertainment: 27
Manga Entertainment: 26
Media Blasters (AnimeWorks, non hentai): 40
Right Stuf (non hentai): 13
Sony Pictures: 4
Synch-Point: 1
Tokyopop: 4
Viz Media: 87
2008
4kiRAB: 4
ADV Films: 103
AnimEigo: 1
Bandai Entertainment: 103
Bandai Visual: 25
FUNimation: 201
Geneon: 35
Manga Entertainment: 6
Media Blasters (AnimeWorks, non hentai): 50
Right Stuf (non hentai): 11
Sony Pictures: 4
Viz Media: 81
Warner Home Video: 7
2009
4kiRAB: 1
ADV Films/Section 23: 80
Bandai Entertainment: 58
Bandai Visual: 4
FUNimation: 196
Geneon: 24
Manga Entertainment: 3
Media Blasters (AnimeWorks, non hentai): 48
Right Stuf (non hentai): 12
Sony Pictures: 9
Viz Media: 69
Warner Home Video: 40
NOTE: Some titles on the list may have some overlap in more than one company; for example, a 4kiRAB title may have been co-released by FUNi and thus is counted in both categories. Same deal with titles released by both Viz and Warner (ex: Anything 2009 and newer), as well as titles which were rescued by another company (ex: Many of Geneon's titles that are now at FUNi, like Black Lagoon).
NOTE 2: I'm aware this list doesn't take into account how many of these are brand new series and which are simply re-releases of old material. After all, if we're only counting new titles, ADV's nurabers from about 2008-2009 would be MUCH lower. This is just tracking how many total DVRAB were released in a given period.
NOTE 3: This doesn't include VHS.
1997
Geneon (called Pioneer at this time): 3
1998
AnimEigo: 1
Central Park Media: 9
Geneon (called Pioneer at this time): 9
Viz Media: 4
1999
ADV Films: 6
AnimEigo: 3
Central Park Media: 6
Geneon (called Pioneer at this time): 57
Manga Entertainment: 2
Viz Media: 13
2000
ADV Films: 29
AnimEigo: 3
Bandai Entertainment: 26
Central Park Media: 21
FUNimation: 6
Geneon (called Pioneer at this time): 58
Manga Entertainment: 9
Media Blasters (AnimeWorks, non hentai): 11
Right Stuf (non hentai): 3
Viz Media: 19
Warner Home Video: 2
2001
ADV Films: 85
AnimEigo: 29
Bandai Entertainment: 41
Central Park Media: 50
FUNimation: 26
Geneon (called Pioneer at this time): 80
Manga Entertainment: 12
Media Blasters (AnimeWorks, non hentai): 40
Right Stuf (non hentai): 14
Tokyopop: 6
Viz Media: 25
Warner Home Video: 4
2002
4kiRAB: 5
ADV Films: 98
AnimEigo: 2
Bandai Entertainment: 75
Central Park Media: 33
FUNimation: 57
Geneon (called Pioneer at this time): 85
Manga Entertainment: 10
Media Blasters (AnimeWorks, non hentai): 44
Right Stuf (non hentai): 6
Synch-Point: 2
Tokyopop: 19
Viz Media: 33
2003
4kiRAB: 15
ADV Films: 185
AnimEigo: 37
Bandai Entertainment: 89
Buena Vista: 5
Central Park Media: 84
FUNimation: 72
Geneon (also Pioneer): 108
Manga Entertainment: 19
Media Blasters (AnimeWorks, non hentai): 64
Right Stuf (non hentai): 14
Synch-Point: 2
Tokyopop: 22
Viz Media: 48
Warner Home Video: 2
2004
4kiRAB: 24
ADV Films: 210
AnimEigo: 21
Bandai Entertainment: 102
Buena Vista: 1
Central Park Media: 46
FUNimation: 88
Geneon (also Pioneer): 174
Manga Entertainment: 8
Media Blasters (AnimeWorks, non hentai): 55
Right Stuf (non hentai): 11
Synch-Point: 2
Tokyopop: 12
Viz Media: 52
Warner Home Video: 2
2005
4kiRAB: 13
ADV Films: 222
AnimEigo: 23
Bandai Entertainment: 110
Buena Vista: 8
Central Park Media: 18
FUNimation: 103
Geneon: 216
Manga Entertainment: 19
Media Blasters (AnimeWorks, non hentai): 54
Right Stuf (non hentai): 13
Sony Pictures: 3
Synch-Point: 5
Tokyopop: 12
Viz Media: 51
2006
4kiRAB: 13
ADV Films: 133
AnimEigo: 17
Bandai Entertainment: 111
Bandai Visual: 4
Buena Vista: 3
Central Park Media: 13
FUNimation: 140
Geneon: 143
Manga Entertainment: 18
Media Blasters (AnimeWorks, non hentai): 42
Right Stuf (non hentai): 15
Synch-Point: 1
Viz Media: 83
2007
4kiRAB: 13
ADV Films: 129
AnimEigo: 1
Bandai Entertainment: 81
Bandai Visual: 23
FUNimation: 190
Geneon: 127
ImaginAsian Entertainment: 27
Manga Entertainment: 26
Media Blasters (AnimeWorks, non hentai): 40
Right Stuf (non hentai): 13
Sony Pictures: 4
Synch-Point: 1
Tokyopop: 4
Viz Media: 87
2008
4kiRAB: 4
ADV Films: 103
AnimEigo: 1
Bandai Entertainment: 103
Bandai Visual: 25
FUNimation: 201
Geneon: 35
Manga Entertainment: 6
Media Blasters (AnimeWorks, non hentai): 50
Right Stuf (non hentai): 11
Sony Pictures: 4
Viz Media: 81
Warner Home Video: 7
2009
4kiRAB: 1
ADV Films/Section 23: 80
Bandai Entertainment: 58
Bandai Visual: 4
FUNimation: 196
Geneon: 24
Manga Entertainment: 3
Media Blasters (AnimeWorks, non hentai): 48
Right Stuf (non hentai): 12
Sony Pictures: 9
Viz Media: 69
Warner Home Video: 40
NOTE: Some titles on the list may have some overlap in more than one company; for example, a 4kiRAB title may have been co-released by FUNi and thus is counted in both categories. Same deal with titles released by both Viz and Warner (ex: Anything 2009 and newer), as well as titles which were rescued by another company (ex: Many of Geneon's titles that are now at FUNi, like Black Lagoon).
NOTE 2: I'm aware this list doesn't take into account how many of these are brand new series and which are simply re-releases of old material. After all, if we're only counting new titles, ADV's nurabers from about 2008-2009 would be MUCH lower. This is just tracking how many total DVRAB were released in a given period.
NOTE 3: This doesn't include VHS.