excel formula sumproduct and age ranges

[Tina]

I really hope someone can help as I am a novice at anything other than the
simplest Excel formula!

I want to calculate the age of customers per month in clusters for ages -
for example in March 08 I want to know how many were 18-24, how many were
25-40 etc etc. I have been using sumproduct for loads of other calculations
as follows

=SUMPRODUCT(--(MONTH('2008'!$L$2:$L$2000)=3))

but I dont know how to link on the additional query for age groups.

Thanks

Tina

 

[M Kan]

Add a helper column to convert the age into an age group, then use a VLOOKUP
formula, withOUT exact match to class each age into a group. Use that column
in your SUMPRODUCT formula

 

[Bob Phillips]

18-24

=SUMPRODUCT(--(DATEDIF(rng_DoBs,TODAY(),"Y")>=18),--(DATEDIF(rng_DoBs,TODAY(),"Y")<24))

etc.

 

[Tina]

I dont really understand these answers - sorry. The data is by age rather
than date of birth, and I dont want them updated so that I know what age they
were when our service was used. I was hoping to link on to the end of the
sumproduct formula something like >=18<=24 or use COUNTIF(OR) or IF(OR) for
the different ages so that the total number of people having that age range
in that month would be counted.