Excel merge two lists - excel

Question

I have two Excel lists:
One extensive with 20 thousand lines. In which:
Two columns are important: First: Unique ID, Second: a value (number formatted).
It can be a value that appears several times, or only once.
I have to create the second list. In this list I have only one column of values that I would like to have.
I need a formula that will look for values from List 2 in List 1 and then match a Unique ID to each value.
It is important that, when no direct value exist. In this case it has to search for a sample which is in about 3-5% value deviation.
Example: there was no value 127, but within 3%, 125 was found.
I've tried indexing and comparison, but it does not seem to work.
VLOOKUP worked, but without 3-5% deviation
I am very grateful for the help.
Example: http://www.filedropper.com/excellist1and2

Answer 1

If the value exists in the list, you can use VLOOKUP or INDEX(MATCH to find it - that's the easy part. If the value is not in the list, then you need to find the nearest value.
The nearest "low" value will be the MAX value ≤ our input, and the nearest "high" value will be the MIN value ≥ our input.
If you have Office 365, you can use MINIFS($D$1:$D$6,$D$1:$D$6,">="&B1,$D$1:$D$6,"<="&(B1*1.05)) and MAXIFS($D$1:$D$6,$D$1:$D$6,"<="&B1,$D$1:$D$6,">="&(B1*0.95)) )` here. If not, you'll need an Array Formula, we can build that "±5%" in early, to simplify the formula.
Starting with the Low values, we want the MAX value ≤ our input and ≥ 95% of our input. Putting an Array Formula in a SUMPRODUCT so that we can use it in a normal formula, we get =SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$1:$D$6>=(B1*0.95))))
The High values are slightly harder, because we can't just multiply be 0 to cancel out anything too low, or over 105% of the target. We need to add a huge number like 1E+99 (a 1 with ninty-nine 0s after it) instead, so that the MIN will ignore them: SUMPRODUCT(MIN($D$1:$D$6+1E+99*(--($D$1:$D$6<B1)+--($D$1:$D$6>(B1*1.05)))))
The last steps are to decide which of these numbers is closer to the target, and then to find the Unique ID to match. The %closeness calculations are (TARGET - LOW)/TARGET and (HIGH - TARGET)/TARGET), and subtracting one from the other gives you 2-(HIGH + LOW)/TARGET - a Positive number means "High" is closer, a Negative number means that "Low" is closer, and 0 means they are both the same distance (I'll default this to the Low number). We then use SIGN to change it to ±1, add 2 to get 1,2 or 3 and finish up with CHOOSE to output our number. In pseudo-code, CHOOSE(2+SIGN(2-(HIGH+LOW)/TARGET),LOW,LOW,HIGH), and the full thing:
CHOOSE(2+SIGN(2-(SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95)))+SUMPRODUCT(MIN($D$1:$D$6+1E+99*(--($D$1:$D$6<B1)+--($D$1:$D$6>(B1*1.05))))))/B1),SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95))),SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95))),SUMPRODUCT(MIN($D$1:$D$6+1E+99*(--($D$1:$D$6<B1)+--($D$1:$D$6>(B1*1.05))))))
Now, we have a number. All we need to do is either use VLOOKUP, or use MATCH to get the row it is on, and INDEX to pull the data for that row:
Office 365:
=IFERROR(VLOOKUP(B1,$D$1:$E$6,2,FALSE),VLOOKUP(CHOOSE(2+SIGN(2-(MAXIFS($D$1:$D$6,$D$1:$D$6,"<="&B1,$D$1:$D$6,">="&(B1*0.95))+MINIFS($D$1:$D$6,$D$1:$D$6,">="&B1,$D$1:$D$6,"<="&(B1*1.05)))/B1),MAXIFS($D$1:$D$6,$D$1:$D$6,"<="&B1,$D$1:$D$6,">="&(B1*0.95)),MAXIFS($D$1:$D$6,$D$1:$D$6,"<="&B1,$D$1:$D$6,">="&(B1*0.95)),MINIFS($D$1:$D$6,$D$1:$D$6,">="&B1,$D$1:$D$6,"<="&(B1*1.05))),$D$1:E$7,2,FALSE))
Otherwise:
=IFERROR(VLOOKUP(B1,$D$1:$E$6,2,FALSE),VLOOKUP(CHOOSE(2+SIGN(2-(SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95)))+SUMPRODUCT(MIN($D$1:$D$6+1E+99*(--($D$1:$D$6<B1)+--($D$1:$D$6>(B1*1.05))))))/B1),SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95))),SUMPRODUCT(MAX($D$1:$D$6*--($D$1:$D$6<=B1)*--($D$6>B1*0.95))),SUMPRODUCT(MIN($D$1:$D$6+1E+99*(--($D$1:$D$6<B1)+--($D$1:$D$6>(B1*1.05)))))),$D$1:E$7,2,FALSE))
(Obviously, change $D$1:$D$6 and $D$1:$E$6 to your actual data table ranges, and B1 to the input-value range)