See attached - tab [rslt (not elegant)] col [MyCalc].rnWord of caution - there are loads of MUCH BETTER way of doing that than the way I did it. The point is I wanted to practice with List.Acumulate and therefore did this long-winded way. But it seems to work 🙂

As a variant, I created a new smaller table (starting with a reference to the larger table) with just the Team, H2H Score and PointsBehind, and assuming you would want to keep your table with empty rows between the "match-ups". See attached.

If you want to integrate it in the larger table, I trust you can achieve that yourself.

Thank you both.  Just an initial look, while it does achieve the objective, there are a few steps I am not familiar with so want to review more to try and learn the concept as it may tie into my final column.  

Along the very same lines, my final column, I need it to calculate a "bonus" for an opponent who achieves a "H2H "Score" of 300 or more.  Thus, in the examples provided, if I took the Assassins and Mullz's Malcontents matchup, if Assassins scored 300 or more, I need a column labeled "Opponent Bonus" that calculates a bonus based upon 1.5% any amount over 300 of their opponent.

As an example.  Assassins H2H Score is 400.  I need a column showing a bonus of 1.5 (100*1.5%) for Mullz's Malcontents. 

Mullz's Malcotents H2H Score is 500.  I need the bonus to show 3 (200*1.5%) for Assassins.

It does not make sense but what I am to setup.  Thanks.  

Added a formula similar to PointsBehind for the Bonus. Tested it by hard-coding some H2H values, although they were overwritten upon refresh. But I did get the 1.5 and 3 as you described.

The entire script now looks like this:

Also uploaded a revised file.

Both appear to work very well.  The problem I have is, I am "good" with the understanding once I break this out until the code within the "if" / "then" statement.  Yes, it works; I just wish I understood why but I just am not experienced enough.  

Thank you very, very much.  I had no idea how to get this accomplished.  I am amazed at the knowledge here.  Again, thank you.  

Quick note here as I finally could test the last part with the "bonus" applied for anything over 300.  There appears to be some "rounding" issues as one example for a score of 381.833 which should return a "bonus" of 1.227 (81.833 * 1.5%) is actually returning 1.228.  Seems like power query rounds down for "5" instead of up.  For example, the actual number here is 1.227495 and rounding to the thousand (i.e. 3 spots) should be 1.227 instead of 1.228. 

Could it be that the 81.833 in fact is 81.8333333333333333333? 1.5% of the latter equals 1.22750, which would round to become 1.228. Not sure how accurate PQ works in these circumstances, though.

Looks that way.  Is there a way, within the "bonus" calculation formula to add a "round" feature to use the figure of 81.833 to multiply to the 1.5% to obtain a figure of 1.227495, which I could round to 1.227?

I know how to take the current formula, remove the 1.50% portion of the calculation, generate the 1.227495 result and then round that number to achieve the expected resulted (rounded to the thousand position) but was not sure if a way to add it to the current formula as is, saving some steps.

Regardless, I can make this work.

You can wrap the relevant parts of bonus calculation in the Number.Round function, like this:

( Number.Round ( PtsBehind[H2H Score]{[Index]+1} , 3 ) - 300 ) * 0.015

Tried by replacing a value to 381.8333333333. The formula returned 1.227495 and then rounded the column to 3 decimals to end up with 1.227.

For the most part, this works.  At least on the one number I was getting the rounding error.  However, for the life of me, I have no idea why power query is taking a number of .4125 and when being told to round to the third digit, it becomes .412.

If I look at the O's and Killer B's matchup, the 27.500 (excess over 300) * 1.5% returns .4125.  I would think that would round to .413.  It does outside of Power Query.    

At this point, the majority is working.  I am just not "sharp" enough to understand some of the little differences.  I never will.  Frustrating.  

I appreciate all the help here.  The "hard part" you got me through.  

Can't explain it either. Sorry!

No worries.  All good help here and very much appreciated.  I would have never figured out the methods provided here for this subject.  The rounding part, another day/topic.  Thanks to all.   

Just a quick note here, incorporating RoundingMode.Up with the Number.Round seems to solve my rounding issue.  

Great! Well done.