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Hello,

I have a set of data points that fall within columns. The columns represent the percentile - as in where this result falls in percentile of population.

For example:

*AgeYears         P3         P5         P7       P10*

5                12.1       13.1       14.1     15.5
7                14.1       14.9        15.9    16.9

On top are column names(p meaning percentile), on bottom are values. Each of these rows would have an 'Age' associated with it.

I am able to easily arrive at percentile for a certain age- as well as finding ratio specific percentile between ages(through a pivot) - however I only have so much age data and want to report on lower/higher ages than I have data for. I know that this is statistically inaccurate to infer, especially in this example of test score - but this is only a sample and am looking more for query guidance.

How can I infer from the data that I do have - ASSUMING AN EVEN RATIO - what percentile a score of 10 for a 4 year old would fall into, relative to 5 years old 3rd percentile being 12.1. If I take the above example and divide 12.1 by 5, I get the percentile by years - but how do I use a pivot which works for finding ratios between percentiles and also for ages that do not have data between 2 rows?

I am able to find the percentiles between 2 ages, but I do not have data for 5 and below and so now I have a pivot which will not work since it returns null for under 5 years old.

Thanks!