> More than 40 million is a lot. For comparison, the US has ~132 million households. Does comparing sales to households make any sense though? You'd need to fi

> More than 40 million is a lot. For comparison, the US has ~132 million households. Does comparing sales to households make any sense though? You'd need to figure out (40MM - Roombas in landfills) / average Roombas per household.