TABLE VI-6.


Costs and returns from most economic
combinations N and P fertilizer for rice,
visiographic estimation, 1970.
Pn = $4.40/kg, Pp= $2.00/kg, Pr= 2.80/kg.


 Levels of Cost of Value of Net
N P Y fert. rice return

 kg/ha -- -- Colombian pesos --

0 0 4400 0 12,320 12,320
37 18 4950 200 13,860 13,660
80 25 5450 400 15,260 14,860
123 30 5930 600 16,604 16,004
166 35 6280 800 17,584 16,784
210 39 6550 1000 18,340 17,340
253 43 6775 1200 18,970 17,770
297 47 6900 1400 19,320 17,920


1.Excluding fixed costs;
cost of fertilizer.


that is, net only of the variable