Manufactured goods, food, and clothing. Note that we tend to think of these things as not being a big deal, but that’s colored by the fact they’re so cheap. In 1970, a wall mount AC was about $400, when the median family income was under $10,000. Lots of people simply could not afford one. Today, a wall mount AC is still $400, while the median family income is over $80,000. People dismiss the fact that an AC unit has gotten 90% cheaper in real terms. But you wouldn’t do that if everyone in your family was huddled around a single AC unit in one room during a southern summer, as was very common in the 1970s.