Wiktionary
conversion rate
n. (context marketing English) The proportion of visitors to a website who take an action desired by the marketers, such as buying a product or subscribing to a newsletter.
Usage examples of "conversion rate".
If you work out the mass conversion rate you will need, you find that even with an ideal photon drive you'll consume the whole mass in a few days.
We could deduce the warping of space-time in the vicinity of supernovae, and we were able to observe the disappearance of a Wolf-Rayet star when its time-conversion rate accelerated.