Ah, they mean 20 percent of the vacuums sold this year. Since a vacuum is not something that gets replaced each year (or every 5 years even?), it will take quite a while for robots to reach 20 percent of all existing vacuums, if ever.
Anecdotally the only person I know who owns a roomba used to work for iRobot.
Anecdotally the only person I know who owns a roomba used to work for iRobot.