time efficient methods for calculations based on different set of data

hi guys,

can anyone guide me on how to calculate averages and standard deviations based on different time periods without having to manually change the cells?

example:
1st average output at z3, 1st std dev output at z4
data to calculate from c3:c50

2nd average output at z5, 2nd std dev output at z6
data to calculate from c51:c98

3rd average output at z7, 3rd std dev output at z8
data to calculate from c99:c148

and it goes on based on this sequence. i would like to know how to do this without having to change the cells each time i want to calculate. basically what is the quickest way to calculate following this sequence?

regards,
ryann

Hi,

2 questions:

1. Could you use helper columns?

2. Your sequence isn't constant. (50 -> 98 is 48 and 98 -> 148 is 50; whereas 3 -> 51 -> 99 is always 48) Can you clarify?

yes ace_XL thanks for noting that error, it should be c99:146

also thanks guys i'll try the methods and will update u all

Thanks guys, it worked. However, I still don't understand the implications of the functions used.

1. Could any of you explain the difference between ace_XL vs Kaper's methods?
2. For each method what does the formula provided mean (functions, range, all calculations)?

Thanks.