Linear Interpolation help

Hi Guys, look:

Cells C3:C36 have a series of dates stretching forward in time
Cells D3:D36 have a series of increasing values corresponding to those dates
Cell A1 has a specific date.

I would like an elegant way for the following: Scan the date range and find the 2 dates in between which my date falls, interpolate linearly using their corresponding values in column D so that I can get an interpolated value for my initial date. Thanks guys!

Can you upload example workbook?
Make sure to avoid personal informations.

Here you go Thanks!

Where do you want output for your result?

Anywhere is fine, say G5

Try something like this:

Formula:

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Unfortunately, this just calculates the midpoint between the values, but I need the interpolation. So that it is accurate on whichever date between.... Im not sure if I am explaining myself well....

Linear interpolation of two points is midpoint.

No. Linear interpolation is finding the straight line which connect two points. This line has an infinite number of y values for infinite number of x values.
The linear interp of coordinates 0,0 and 2,2 is a straight line, and the value of the interpolation will depend on your x. If your x is close to 2, then your y will be close to 2.

Sorry, I missunderstood...

Does this help:

Formula:

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However, this doesnt work when I try to put the formula in another worksheet, I use:

=FORECAST(AY8,OFFSET('MID-SWAP Curve'!$C$2,MATCH(AY8,'MID-SWAP Curve'!$C$3:$C$36,1),1,2),OFFSET('MID-SWAP Curve'!$C$2,MATCH(AY8,'MID-SWAP Curve'!$C$3:$C$36,1),,2))

Somehow the match function gives N/A

Ideas?

It works! However, this doesnt work when I try to put the formula in another worksheet, I use:

=FORECAST(AY8,OFFSET('MID-SWAP Curve'!$C$2,MATCH(AY8,'MID-SWAP Curve'!$C$3:$C$36,1),1,2),OFFSET('MID-SWAP Curve'!$C$2,MATCH(AY8,'MID-SWAP Curve'!$C$3:$C$36,1),,2))

Somehow the match function gives N/A

Ideas?

Is your AY8 in same shwwt or in MID-SWAP sheet?

Because this one works for me:

Formula:

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