Formula to lookup values in a specific cells based on values in other cells in the same column

[Rnkhch]

Hello,

I have a large table that looks like this:

(week)	1	1	1	1	1	2	2	2	2	2	etc
(day)	1	2	3	4	5	1	2	3	4	5	etc
Person1	78	89	91	93	95	93	87	92	90	81	etc
Person2	81	88	77	73	72	84	86	89	85	93	etc
etc.

<tbody>
</tbody>

I would like to define a formula that calculates "weekly score improvement" for each person, by subtracting score of week1/day5 from week1/day1 and repeating this for all subsequent weeks, i.e. for instance:

Person1's improvement in week1 = (the score in week1/day1 column) - (the score in week1/day5 column)

How can I use the week and day identifiers to call values from those columns, for each person?

Any input is highly appreciated! Thanks!

 

[Fluff]

Duplicate https://www.mrexcel.com/forum/excel...lls-based-values-other-cells-same-column.html

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