SPEF file in encounter

I'm trying to simulate coupling capacitance between two interconnect wires response to changing the seprating distance between them in 45nm process.
I found many coupling cap. values between the two nets (each for different node), but only one coupling cap. reacted with changing the distance so that's how I figured the right node between the two wires.

This is the output coupling cap. in SPEF file, does the tool take into consideration the common length between the two wires? or should I multiply the value with the common length between the two coupled wires ?


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Also I made a table that shows the values of the coulping cap. between the two wires vs the separation distance



Are these values logical ? Given the common length and wire widths (two wires are Metal4)...as I think coupling cap. should be hundereds of femto farads.

Thanks