Consecutive repetitions

[Eco]

Hi, I need a formula to count the number of times an Item is repeated in
consecutive days from a list.

For example:
A B C
*******************
1 * Date Item Repeated
2 * 1-jun Item1 1
3 * 1-jun Item2 1
4 * 2-jun Item1 2
5 * 2-jun Item3 1
6 * 3-jun Item1 3
7 * 3-jun Item3 2
8 * 3-jun Item4 1
.....
...
..

NOTES:
- My list contains consecutive days including weekends.
- Each Item is not repeated in the same day.
- Each day, the number of Items appeared could be different.
- My list is ordered by date from the older to the newest.

Thanks in advance for your help.

 

[MartinW]

Hi Eco,

Try this in C2 and drag down as far as is needed.
=COUNTIF($B$2:B2,B2)

HTH
Martin

 

[Eco]

Hi MartinW, the repetitions must be "consecutive repetitions" if one day the
Item is no present de counter stops counting.

Extending the example for better understanding:

Date Item Counter
1-jun Item1 1
1-jun Item2 1
2-jun Item1 2
2-jun Item3 1
3-jun Item1 3
3-jun Item3 2
4-jun Item1 4
5-jun Item3 1 <-- Here, your option will say 3 but must be 1

Thanks anyway.

 

[Guest]

=IF(A2=A$1,1,SUMPRODUCT((A$1:A1=A2-1)*(B$1:B1=B2),C$1:C1)+1)
in C2 and copied down.

Jerry

 

[Eco]

It Doesn't works, I think because in file 1 there are the tittles of each
column. I couldn't manage to adaptate it correctly.

Thanks anyway.

 

[Guest]

Simply change $1 to $2 everywhere in the formula.

Jerry

 

[Eco]

Sorry:
It Doesn't works, I think because in *row 1 there are the tittles of each
column. I couldn't manage to adaptate it correctly.

Thanks anyway.

 

[Guest]

Actually, the outer IF() is unnecessary. You could reduce to simply
=SUMPRODUCT((A1:A$2=A2-1)*(B1:B$2=B2),C1:C$2)+1
in C2 and copied down.

Jerry

 

[Eco]

Great! It really works!!! Thanks a lot Jerry. ))

 

[Guest]

Correct in principle, but in practice you would get a circular reference in
C2. Instead start the formula in C3, where it becomes
=SUMPRODUCT((A$2:A2=A3-1)*(B$2:B2=B3),C$2:C2)+1
copy down, and manually fill C2 with 1.

Jerry

 

[Eco]

I'll take the advice Jerry, thank's again.

Correct in principle, but in practice you would get a circular reference
in
C2. Instead start the formula in C3, where it becomes
=SUMPRODUCT((A$2:A2=A3-1)*(B$2:B2=B3),C$2:C2)+1
copy down, and manually fill C2 with 1.

Jerry