Non-continuous Averages

The formulas I've provided thus far expect the data to be spaced evenly (it uses the time value in the current row, but once that is calculated it then averages cells that are each 4 rows apart. In your latest sample some are two rows apart while others are four. I could create a similar formula that would take that EXACT setup into account, but if anything changed, or you tried dragging it down even 1 row it would fail. It would be a one cell formula, essentially. It would be easier to just manually type in

=AVERAGE(B3,B5,B7,B11,B15)

And to Marvin's point - yes, that would make sense in the last example, although it would still be easier to just use the cell addresses in that case. Using names would likely not work in the earlier example as it is more of a rolling average as you drag the formula down.