| AE | Calculate Agronomic Efficiency |
| ecoNUE | Calculate NUEecology |
| IE | Calculate Internal Efficiency (IE) |
| NBI | Calculate N Balance Intensity (NBI) |
| NdfF | Calculate N derived from Fertilizer (NdfF) |
| NHI | Calculate N Harvest Index (NHI) |
| NP | Calculate Nitrogen Productivity (NP) |
| NRE | Calculate Fertilizer-N Recovery Efficiency |
| NRE15 | Calculate Isotope-Based Recovery Efficiency of N-Fertlizer (NRE15) |
| NUEbal | Calculate NUEbalance |
| NUEcrop | Calculate NUEcrop |
| NUEFC | Calculate NUE of a Food Chain (NUEFC) |
| NUEsoil | Calculate NUEsoil |
| NUEyield | Calculate NUEyield |
| NUpE | Calculate N Uptake Efficiency (NUpE) |
| NUtE | Calculate N Utilization Efficiency (NUtE) |
| PE | Calculate Physiological Efficiency |
| PFP | Calculate Partial-factor Productivity (PFP) |
| PNB | Calculate Partial N Balance |
| sNBI | Calculate N Balance Index of a System (sNBI) |
| sNUE | Calculate NUE of a System (sNUE) |
| TNdfF | Calculate Total N derived from Fertilizer (TNdfF) |
| VNF | Calculate Virtual N Factor (VNF) |