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Calculators BioProduct

How to use this calculator

  1. Base Input
    • Enter biological input application costs.
    • Establish a gross margin: grain price, yield and expected change in income (%) due to biological input use.
    • Limiting factors: only pH has been entered to date (If you enter a pH above 6, then the program will show no benefit / saving to liming). Enter a pH above 6 if you know the product you are trialing does not ameliorate acid soils.
  2. Additional Factors (changes to nutrient/lime requirements etc.):
    • Enter any expected changes in proposed N, P, K and lime requirements. (This section is very subjective and designed for testing ideas, not to be used to provide a prescription.)
  3. Impact of biological inputs:
    • This measures how much of the improvement in profit can be expected to flow after year 1, with options to test when re-application might be desirable. The second part of the calculation is to make judgement on how many years it is feasible to apply the altered level of nutrients. The base assumptions for the model assume a cost saving on inputs of $8.35/ha for 4 years after the application of biological input. Please change this to suit your own property.
    • If you believe biological input effects are nil in any of the ten out-years, enter a “0%” in the years you believe there is no benefit, and uncheck the column asking whether to apply input changes for those years.
  4. Summary – This deducts the cost of the treatment from the benefit expected over five years to assess whether the treatment is considered worth pursuing base on the estimates you have made.

Base Inputs

Application Rate (t/ha)
Costs Product ($/t)
Transport ($/t)
Application ($/t)
Total Cost Per t applied $150.00
Total cost of Product per Ha applied $150.00
Change in Crop Gross Margin
On Farm Grain Price ($/t)
Average Yield ((t/ha)
Total Income $500.00
Expected Change in Yield
Improvement in crop gross margin ($/ha) $50.00
Factor Limiting Saving
Initial Soil pH
Only pH below 6 shows a benefit to lime req

Additional Factors

Kg $/t landed and applied $/ha increase in cost
Change in N Requirements
Change in P Requirements
Change in K Requirements
Change in Lime Requirements
Change In Inputs -$10.95

Impact of Product over 10 Years

Cost of Funds
Improvment in
Gross Margin
Benefit Reapply Product? Apply input
Changes in
Net Benefit
Year 1
-$10.95 $60.95
Year 2
-$10.95 $50.95
Year 3
$139.05 -$109.05
Year 4
-$10.95 $60.95
Year 5
$0.00 $40.00
Year 6
$0.00 $30.00
Year 7
$0.00 $30.00
Year 8
$0.00 $50.00
Year 9
$0.00 $0.00
Year 10
$0.00 $0.00
Total Value of Changes to Income $158.52

Summary of Outcome

Total Product Outlay ($ / ha) $150.00
Present value of change in income ($/ha) $158.52
Net Benefit ($ / ha) $8.52
Proceed with proposed amelioration

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