Sector Ratios

Specialised ratios for industries where standard metrics are insufficient.

SaaS / Software

Import: from fin_ratios.ratios.sector.saas import *

rule_of_40

rule_of_40(revenue_growth_pct, profit_margin_pct) -> float | None

Formula: Revenue Growth % + Profit Margin %. Rule of 40: healthy SaaS companies score ≥ 40.

net_revenue_retention (NRR)

net_revenue_retention(beginning_arr, expansions, contractions, churn) -> float | None

Formula: (Beginning ARR + Expansions − Contractions − Churn) / Beginning ARR. NRR > 120% indicates product-led growth.

magic_number

magic_number(net_new_arr, sales_and_marketing_expense) -> float | None

Formula: Net New ARR / S&M Spend. >0.75 is efficient; >1.0 is excellent.

ltv_cac

ltv_cac(ltv, cac) -> float | None

Formula: LTV / CAC. >3x is healthy.

burn_multiple

burn_multiple(net_burn, net_new_arr) -> float | None

Formula: Net Burn / Net New ARR. Lower is more efficient; >2x warrants attention.

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REIT

Import: from fin_ratios.ratios.sector.reit import *

funds_from_operations (FFO)

funds_from_operations(net_income, depreciation, gains_on_sale=0) -> float | None

Formula: Net Income + Depreciation − Gains on Property Sales. NAREIT standard.

adjusted_ffo (AFFO)

adjusted_ffo(ffo, capex_maintenance, straight_line_rent=0) -> float | None

FFO adjusted for maintenance CapEx and non-cash items.

price_to_ffo

price_to_ffo(market_cap, ffo) -> float | None

REIT equivalent of P/E ratio.

cap_rate

cap_rate(noi, property_value) -> float | None

Formula: NOI / Property Value. Higher cap rate = higher yield but potentially higher risk.

net_operating_income (NOI)

net_operating_income(revenue, operating_expenses) -> float | None

occupancy_rate

occupancy_rate(occupied_units, total_units) -> float | None

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Banking

Import: from fin_ratios.ratios.sector.banking import *

net_interest_margin (NIM)

net_interest_margin(net_interest_income, avg_earning_assets) -> float | None

efficiency_ratio

efficiency_ratio(non_interest_expense, net_revenue) -> float | None

Lower is better. Well-run banks target <55%.

non_performing_loan_ratio (NPL)

non_performing_loan_ratio(non_performing_loans, total_loans) -> float | None

tier1_capital_ratio

tier1_capital_ratio(tier1_capital, risk_weighted_assets) -> float | None

cet1_ratio

cet1_ratio(common_equity_tier1, risk_weighted_assets) -> float | None

Regulatory minimum: 4.5% (Basel III). Well-capitalised: >10%.

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Insurance

Import: from fin_ratios.ratios.sector.insurance import *

loss_ratio

loss_ratio(claims_paid, premiums_earned) -> float | None

Formula: Claims / Premiums. <60% is excellent; >100% means underwriting losses.

expense_ratio

expense_ratio(underwriting_expenses, premiums_written) -> float | None

combined_ratio

combined_ratio(loss_ratio, expense_ratio) -> float | None

Formula: Loss Ratio + Expense Ratio. <100% = underwriting profit; >100% = loss.

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TypeScript

import { ruleOf40, netRevenueRetention } from 'fin-ratios'
import { fundsFromOperations, capRate } from 'fin-ratios'

ruleOf40({ revenueGrowthPct: 35, profitMarginPct: 12 })  // 47 (healthy)
capRate({ noi: 5e6, propertyValue: 70e6 })               // 0.071