Table 7: Marginal rate of return (MRR) and Sensitivity analysis to establish the profitability of onion to nitrogen and phosphorus.


Yld=Yield; Ajy=adjusted yield; GFB=Gross field benefit; NB=Net benefit; C.TC=change in total cost; C.NB=change in net benefit; MRR=Marginal rate of return; TSP=Triple Super phosphate; TVC=Total variable cost
Treatment Ajy
(t/ha)		 Urea
(birr)		 TSP
(birr)		 Labor
(birr)		 TVC NB C.TC C.NB MRR(%)
N0P0 19.97 0 0 0 0 158281.50
N34.5P0 21.99 562.5 0 18.75 581 175353.00 581 17071.50 2937.0
N34.5P46 23.99 562.5 950 43.75 1556 190328.25 975 14975.25 1535.9
N0P92 24.16 0 1900 50 1950 191359.50 394 1031.25 261.9
N69P46 25.40 1125 950 62.5 2138 201073.50 188 9714.00 5180.8
N138P0 25.83 2250 0 75 2325 204313.50 188 3240.00 1728.0
N103.5P46 26.69 1687.5 950 81.25 2719 210821.63 394 6508.12 1652.9
N103.5P92 29.02 1687.5 1900 106.25 3694 228503.25 975 17681.63 1813.5
N103.5P138 31.15 1687.5 2850 131.25 4669 244491.75 975 15988.50 1639.8