Average Interval In Corresponding Data?

I have geological readings "W,X,Y & Z". For every drilled hole I have these readings recorded for individual intervals (i.e. 1-2m, 2-3m, etc.)

However, the intervals have now been grouped together based on other (unlisted) specifications.

Now I am tasked with averaging these readings "W,X,Y & Z" for the decided groupings. For example.... if intervals 1-4m have been grouped for the first hole, what is the average reading of "W,X,Y & Z" over this new interval?

I have attached a file which displays the layout of the spread. To the left is the original data, and in columns I:K are the new 'groupings' of intervals. Ideally, I would like to generate the average table to the right of the original data (highlighted in green).

So basically, I need some vba code to average the readings in the 1st table conditionally to correspond with the grouped intervals in the 2nd table.