Hi everyone,

I have two lists of data - one showing fuel weights at 67 lb increments from
0 up to 3645 lbs (sometimes at different increments for special weights) and
the other showing a corresponding moment (weight times the distance of that
weight from the center of gravity). These come from an aircraft weight and
balance manual. As you can tell, for a specific fuel weight not listed in
this manual, one has to interpolate between two listed values in order to
estimate a moment value for that unlisted weight.

I'm trying to come up with a very precise formula using excel that will
accurately estimate the moment for a specific fuel weight, but the arm
(distance from the cg) varies for each fuel weight in a non-linear manner.
Using a trendline from a chart, the closest R^2 value I can come up with is
0.999811266 (which still yields up to a 5% error).

Is there any excel tool or trick that can help revise this formula and make
it more precise? Thanks for any help.