There is a published sticker price, but I don't think anyone outside of tiny installs with just a few users pays that... it's very much the enterprise sales model of "let's schedule a call and talk about it." They also for many years would let previously negotiated prices stand during renewals even when sticker price went up, so older orgs often have the "same" license being charged at many different prices based on when it was first purchased and how the negotiations went at the time.