Mateusz Gruszczyński
59 lines
2.4 KiB
Python
59 lines
2.4 KiB
Python
from decimal import Decimal, ROUND_HALF_UP
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def money(value):
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return Decimal(str(value)).quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
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def calculate_costs(gross, vat_rate=23, vat_deduction_percent=50):
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gross = Decimal(str(gross)); rate = Decimal(str(vat_rate))
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deduction = Decimal(str(vat_deduction_percent)) / Decimal("100")
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net = gross / (Decimal("1") + rate / Decimal("100")); vat = gross - net
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deductible_vat = vat * deduction
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return {"gross": money(gross), "net": money(net), "vat": money(vat),
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"deductible_vat": money(deductible_vat), "final_cost": money(gross - deductible_vat)}
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def calculate_net_price_costs(net_price, vat_rate=23, vat_deduction_percent=50):
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"""Return per-unit invoice and effective costs for a net fuel price.
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A 50% VAT deduction means the company bears half of the VAT, not a 50% VAT rate.
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"""
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net = Decimal(str(net_price))
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rate = Decimal(str(vat_rate)) / Decimal("100")
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deduction = Decimal(str(vat_deduction_percent)) / Decimal("100")
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deduction = min(max(deduction, Decimal("0")), Decimal("1"))
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vat = net * rate
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invoice_gross = net + vat
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deductible_vat = vat * deduction
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effective_cost = invoice_gross - deductible_vat
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return {
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"net": net,
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"vat": vat,
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"invoice_gross": invoice_gross,
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"deductible_vat": deductible_vat,
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"effective_cost": effective_cost,
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}
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def calculate_net_price_comparison(retail_gross_price, settlement_net_price, liters=1, vat_rate=23):
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"""Compare retail and settlement prices on a net-to-net basis.
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Retail price is supplied gross (pump price), while settlement/Last Price is net.
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VAT is excluded from the saving because recoverable tax is not a commercial saving.
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"""
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retail_gross = Decimal(str(retail_gross_price))
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settlement_net = Decimal(str(settlement_net_price))
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quantity = Decimal(str(liters))
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rate = Decimal(str(vat_rate)) / Decimal("100")
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retail_net = retail_gross / (Decimal("1") + rate)
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saving_per_liter = max(retail_net - settlement_net, Decimal("0"))
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return {
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"retail_net_price": retail_net,
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"settlement_net_price": settlement_net,
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"saving_net_per_liter": saving_per_liter,
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"retail_net_total": retail_net * quantity,
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"settlement_net_total": settlement_net * quantity,
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"saving_net_total": saving_per_liter * quantity,
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}
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