This app is designed to assist producers in selecting a nitrogen (N) rate that improves profitability when nitrogen and corn prices fluctuate. Maximum return to N (MRTN) is the N rate that will be most profitable for a particular N:Corn price ratio. The MRTN rate is the large number expressed in lbs N/acre at the bottom of the screen, and is the total N rate recommended for your field. From this number, you need to subtract the lbs N/acre starter you apply and subtract the lbs N/acre N credits you take. Below the single large number is the range of N rates that result in profitability within $1/acre of the MRTN rate.