One bushel of corn requires 1.12 pounds of nitrogen and is is the base to determine application rates based on yield goals for next year's crop.  The corn plant gets N from carryover in the soil, applied N, and OM mineralization (20-30 pounds/point) which reduce down that 1.12 factor when considering application rate.  One also needs to subtract N loss from leaching, denitrification, volatilization, and tie-up in high carbon residue such as corn-on-corn.  Doing all that, one will arrive at a common 0.8 to 1.0 per bushel application rate.  For the above side by side test, one could argue the carryover, mineralization, and losses are a wash so the 1.12 can be used.

Doing some math for 2025:

200 bu/ac x 1.12 pounds of N = 224 pounds of N required

Average for my fields based on grid soil sampling Fall of 2024:

Subtract 35 pounds of carryover N
Subtract 25 pounds x 5% OM = 125 pounds of N mineralization

Therefore 224 required, minus 35 carryover, minus 125 mineralization = 64 pounds of N need to be applied, plus X amount for the losses.

The more tricky part of the equation are the losses.  Is the 35 pounds measured last fall still going to be there in the spring and especially summer when the corn needs it?  How much will it rain between spring frost thaw and black-layer?  How much is tied up in breaking down residue of 5+ year COC?