excel incrementing answers

[Arnoux]

Good day.

I need help with the following please.

I have a lot of values in column j,k,l . like for instance.
Column.......J .......K .......L .........M.........................N.....................O
.................1 ...... 5 ......4
.................8 ...... 7 ......3
.................2....... 7.......8
............................................................................
row 17.......2.........5......7
row 18.......2.........5......7.......=min(J1:j20)...=min(K1:k20)...=min(L1:l20)
row 19.......2.........5......7.......=max(J1:j20)...=max(K1:k20)...=max(L1:l20)
row 20.......2.........5......7.......=AVE(J1:j20)...=AVE(K1:k20).....=AVE(L1:l20)
row 21.......2.........5......7 .............................======> #1 of new set of 20 values ( at row 40 new Average)
row 22

(etc)
this goes on forever.

Now my problem is. I need to work out the Min Max and average value every 20'th data value in column J ,K,L, and I need the answer to appear in J-M K-N L-O underneath
I wrote an =if equation but my data for min and max are skewed when I fill it through the rest of my data. !!!

I hope you understand.

Please help I will send you a picture of my data if needed.

Thank you
Arnoux

[NBVC]

If I understood correctly, try this formula in M1:

=IF(MOD(ROWS(J$1:J1),20)=18,MIN(OFFSET(J1,-17,,20,1)),IF(MOD(ROWS(J$1:J1),20)=19,MAX(OFFSET(J1,-18,,20,1)),IF(MOD(ROWS(J$1:J1),20)=0,AVERAGE(OFFSET(J1,-19,,20,1)),"")))

copied across to O1 and then down the rows to the bottom of the dataset. Every 18th to 20th row will have results.

[Arnoux]

Hi NBVC. Thanks for the help.The function works perfectly. You are an absolute genius. Well done