arebelspy: and by average return im refering to the average return of a 1 year investment in a broad index in any given year over the past years (for which data is available).

How is that different than the 1-year return?

And what is a min. return for 1 year? And how would it be different than the max return?

You wrote:

1st year: min. return, max. return, average return, median

Or did you just mean the low point for the year, the high point, and the average point? Or ending point?

All of those make sense over a time period, but you need a shorter time interval for that to be the case. E.g. monthly returns over one year, or yearly returns over a 5 year period. Min/max/median then makes sense. But just looking at a 1 year timeframe compared to itself min=max=avg.. there's just the one return for the year.

/still confused.