The criteria that makes a category of life expense "ordinary" (IIRC) is that the majority of households spend income on it, so it includes things like taxes, healthcare, and mobile phones. Typical American life as revealed by actual expenditure patterns, and BLS breaks each category down by income decile.
I can't find precise data on retirement outflows and there are many possible ways to account for it (e.g. is Social Security contribution considered saving for retirement?) but what I can find seems to indicate that the majority of Americans do save for retirement, which would suggest it is an ordinary expense.
The only category of "non-ordinary" that I recall being surprising was eating out at restaurants. I should know better, almost no one ate out at restaurants when and where I grew up, but my perspective has clearly been skewed over time by my own lifestyle.
I can't find precise data on retirement outflows and there are many possible ways to account for it (e.g. is Social Security contribution considered saving for retirement?) but what I can find seems to indicate that the majority of Americans do save for retirement, which would suggest it is an ordinary expense.
The only category of "non-ordinary" that I recall being surprising was eating out at restaurants. I should know better, almost no one ate out at restaurants when and where I grew up, but my perspective has clearly been skewed over time by my own lifestyle.