The growth in the number of elderly depresses median household income. Normalizing for the size of household radically changes the picture. For households of one person, the median income peaked in 1989, but from 1970 to 1996 increased by 52 per cent. For four-person households, the real increase was 26 per cent. Other factors further depress the apparent increase in household income.
Immigrants typically have lower incomes.
Increased immigration may reduce median household income in a way that does not necessarily reflect on the state of the economy. The Consumer Price Index used to normalize income is generally considered to have technical problems. In some cases, it does not appropriately consider the improvement in products. If a car increases in both price and reliability, not all of the increase is really inflation. The consumer in some sense is getting more car.