# Thread: Formula for data set that increases daily

1. ## Formula for data set that increases daily

I know this is an easy one. Just shows you need math after all!

I need to figure out the formula to use in order to project out how much space will be needed for a data project.
Baseline of 22,000 files
This increases by 100 each day
Size is 80,000 per file

How would I formulate that so I can figure out where it would be in 20 days, 50 days, 120 days, etc.? I'm ultimately going to put this into Excel.

Thanks for the help!

2. ## Re: Formula for data set that increases daily

After d days, the number of files would be 22000+ 100d. The size would be 80000(22000+ 100d).

3. ## Re: Formula for data set that increases daily

I had that....but I need to add that 100 per day to the calculation. Sort of like compound interest.

Day 1 = 22000
Day 2 = 22000 + 100 = 22100
Day 3 = 22100 + 100 = 22200
Day 4 = 22200 + 100 = 22300

I can do it the hard way in Excel.

4. ## Re: Formula for data set that increases daily

Originally Posted by mvalpreda
I had that....but I need to add that 100 per day to the calculation. Sort of like compound interest.
Day 1 = 22000
Day 2 = 22000 + 100 = 22100
Day 3 = 22100 + 100 = 22200
Day 4 = 22200 + 100 = 22300
I can do it the hard way in Excel.
Halls gave you the proper formula. Do you not see how it works?
Your example is d=3: 3 days later; 22000 + 100d = 22000 + 100(3) = 22000 + 300 = 22300.

5. ## Re: Formula for data set that increases daily

Yes, I just realized I'm an idiot. I was over-thinking it and for some reason was thinking it was percentage and not an absolute number.

I had it figured out on my own before. Derp.

6. ## Re: Formula for data set that increases daily

STOP IT! We've all done something like that before !