Barbara didn't get her first Batgirl book until Vol 3??

[SixSpeedSamurai]

Where would Barbara's Batgirl Year One mini-series fall into that equation?

Since the title was Batgirl "Year One" I don't think it counts as a Batgirl Vol X book.

[Jim Kelly]

DC didn't put out that many ongoing titles in the 1970s and a lot of the ones they did put out were bi-monthly (only six issues per year). Believe it or not, Batman had gone down in popularity. Remember these were mass market comic books--not specialty shop--and they had to sell in higher numbers to stay alive.

And then came the DC Implosion. DC had planned to expand their line with the SUPERMAN movie, but Warner turned around and decided they needed to cut a bunch of titles. They wanted DC to cut DETECTIVE COMICS, but keep BATMAN FAMILY because it had better sales. However, the staff at DC convinced them to let DETECTIVE survive if they rolled BATMAN FAMILY into that title, which they did.

Since Batgirl was featured in DETECTIVE or BATMAN FAMILY for most of the 1970s, she was doing pretty good for herself--relative to other DC super-heroes who either got chopped or never had a regular gig in a comic book.