Now, I do understand that babies are technically produced rather than consumed, but I would hope that, in this age of medicine, the supply and demand for babies at least approximately equalizes. In this way, we can talk about them as either normal goods – goods where demand for them increases as income increases – or inferior goods – goods where demand decreases as income rises. (See here for a video refresher on the determinants of demand.) On a macroeconomic level, normal and inferior goods are roughly equivalent to cyclical assets, which rise in value during good economic times, and countercyclical assets, which rise in value during bad economic times, respectively.