One of the few advantages of pumping full time is that you know exactly how much milk your baby is getting. I typically pumped about 22-25 ounces a day with K, but she nursed over night so I never knew precisely how much she was eating.
With Alec though, I'm pumping it all, so I know precisely how much I make. I'm currently producing 28-30 ounces a day, which is almost a quart of milk a day. Moo indeed.