dynamics with index or offset

[dmheller]

All,
This is in the pre planning stage but I want to know if I can do it before I move forward with it. I have to calculate emissions from a source, the source gets tested and the emission factor changes. I want a dynamic table with dates and factors and I want to know if there is an equation that I can say look up the date and the emission value and calculate it. I know index will look back if I put I -1 so that might be my best option. Any thoughts?

 

[AFPathfinder]

You would use two sets of INDEX/MATCH functions to lookup the date and emission separately within the same formula, but I'm not sure what type of calculation would use a date and an emission value in the equation. In my experience, I usually keep the lookup functions just pulling in the values in separate columns, then have another column do the calculations for the sake of readability if I ever needed to fix the formulas. But, you can squeeze it all into a single formula under column constraints.