4. Financial Ratios — From Numbers to Meaning

With time series data, financial ratios can be calculated. DartLab automatically computes 30+ ratios across 6 categories.

Two modes:

1. Company.ratios — Financial ratios time-series DataFrame (metric × period, newest first)
2. Company.finance.ratios — Latest single-period RatioResult (TTM + latest balances)

7 categories:

• Profitability (8): ROE, ROA, operating margin, net margin, gross margin, EBITDA margin, COGS ratio, SG&A ratio
• Stability (7): Debt ratio, current ratio, quick ratio, equity ratio, interest coverage, net debt ratio, non-current ratio
• Growth (6): Revenue growth, operating income growth, net income growth, asset growth, equity growth, 3-year CAGR
• Efficiency (4): Total asset turnover, inventory turnover, receivables turnover, payables turnover
• Cash Flow (5): FCF, operating CF margin, operating CF/net income, CAPEX ratio, dividend payout ratio
• Valuation (5): PER, PBR, PSR, EV/EBITDA, market cap (requires market cap input)
• Composite (8): O-Score, Z”-Score, Springate, Zmijewski, Beneish M-Score, Sloan Accrual, Piotroski F-Score, Income Quality

Setup

import dartlab

c = dartlab.Company("005930")

Ratios Time Series

Company.ratios returns a financial ratios time-series DataFrame. Rows are metrics, columns are periods, newest first.

r = c.ratios  # DataFrame (ratio × period, newest first)

For the latest single-period RatioResult, use c.finance.ratios:

rr = c.finance.ratios  # RatioResult (TTM + latest balances)

If ratios is None, the company lacks sufficient financial data.

r = c.ratios
if r is None:
    print("Cannot calculate financial ratios")

Profitability Metrics (8)

Measures how much the company keeps from what it earns.

ROE (Return on Equity)

Net Income ÷ Equity × 100

Shows how much was earned relative to shareholder-invested capital. One of the most important profitability metrics for investors.

print(f"ROE: {r.roe:.1f}%")

A high ROE isn’t always good. If a company uses heavy debt to keep equity small, ROE can be artificially inflated. Always check alongside the debt ratio.

ROA (Return on Assets)

Net Income ÷ Total Assets × 100

Shows how efficiently total assets are being utilized.

print(f"ROA: {r.roa:.1f}%")

Operating Margin

Operating Income ÷ Revenue × 100

Core business profitability. Shows pure operating performance excluding interest, taxes, and one-time items.

print(f"Operating Margin: {r.operatingMargin:.1f}%")

Net Margin

Net Income ÷ Revenue × 100

print(f"Net Margin: {r.netMargin:.1f}%")

A large gap between operating and net margin suggests significant interest costs, FX losses, or one-time expenses.

Gross Margin

Gross Profit ÷ Revenue × 100

Pure margin after deducting cost of goods. Higher means stronger pricing power.

if r.grossMargin:
    print(f"Gross Margin: {r.grossMargin:.1f}%")

EBITDA Margin

(Operating Income + Estimated Depreciation) ÷ Revenue × 100

Useful for comparing profitability of capital-intensive companies. Depreciation is estimated as tangible assets × 5% + intangible assets × 10%.

if r.ebitdaMargin:
    print(f"EBITDA Margin: {r.ebitdaMargin:.1f}%")

COGS Ratio

Cost of Sales ÷ Revenue × 100

if r.costOfSalesRatio:
    print(f"COGS Ratio: {r.costOfSalesRatio:.1f}%")

COGS ratio + gross margin = 100%. A high COGS ratio indicates intense price competition or high raw material dependency.

SG&A Ratio

Selling, General & Administrative Expenses ÷ Revenue × 100

if r.sgaRatio:
    print(f"SG&A Ratio: {r.sgaRatio:.1f}%")

SG&A includes labor, marketing, R&D, and depreciation costs.

Stability Metrics (7)

Measures a company’s financial soundness — “how safe is it?”

Debt Ratio

Total Liabilities ÷ Equity × 100

The ratio of borrowed money to own money.

print(f"Debt Ratio: {r.debtRatio:.1f}%")

Appropriate levels vary by industry. 200% is normal for construction; 100% is high for IT.

Current Ratio

Current Assets ÷ Current Liabilities × 100

Shows whether debts due within 1 year can be covered by assets convertible to cash within 1 year.

print(f"Current Ratio: {r.currentRatio:.1f}%")

Quick Ratio

(Current Assets − Inventory) ÷ Current Liabilities × 100

A more conservative liquidity measure that excludes inventory. Useful for industries where inventory is hard to liquidate quickly.

if r.quickRatio:
    print(f"Quick Ratio: {r.quickRatio:.1f}%")

Equity Ratio

Equity ÷ Total Assets × 100

The proportion of total assets funded by own capital. Inverse concept of debt ratio.

if r.equityRatio:
    print(f"Equity Ratio: {r.equityRatio:.1f}%")

Interest Coverage Ratio

Operating Income ÷ Interest Expense

Shows how many times operating income can cover interest payments. Below 1x means the company can’t even pay interest.

if r.interestCoverage:
    print(f"Interest Coverage: {r.interestCoverage:.1f}x")

Net Debt Ratio

Net Debt ÷ Equity × 100

Net debt = short-term borrowings + long-term borrowings + bonds − cash equivalents. Negative means cash exceeds borrowings (debt-free management).

if r.netDebtRatio is not None:
    print(f"Net Debt Ratio: {r.netDebtRatio:.1f}%")

Non-Current Ratio

Non-Current Assets ÷ Equity × 100

Shows how much of long-term assets are funded by own capital. Over 100% means external capital is used for long-term asset acquisition.

if r.noncurrentRatio:
    print(f"Non-Current Ratio: {r.noncurrentRatio:.1f}%")

Efficiency Metrics (4)

Measures how efficiently assets are utilized.

Total Asset Turnover

Revenue ÷ Total Assets

How much revenue is generated per unit of assets. Higher = more efficient asset utilization.

if r.totalAssetTurnover:
    print(f"Total Asset Turnover: {r.totalAssetTurnover:.2f}x")

Inventory Turnover

Revenue ÷ Inventory

How many times inventory turns over in a year. Higher = more efficient inventory management.

if r.inventoryTurnover:
    print(f"Inventory Turnover: {r.inventoryTurnover:.1f}x")

Receivables Turnover

Revenue ÷ Trade Receivables

How quickly credit sales are collected.

if r.receivablesTurnover:
    print(f"Receivables Turnover: {r.receivablesTurnover:.1f}x")

Payables Turnover

Cost of Sales ÷ Trade Payables

How quickly trade payables are settled.

if r.payablesTurnover:
    print(f"Payables Turnover: {r.payablesTurnover:.1f}x")

Cash Flow Metrics (5)

Profit is an accounting number; cash flow is real money in and out. Profitable companies can still go bankrupt without cash.

FCF (Free Cash Flow)

Operating Cash Flow − CAPEX

Cash remaining after subtracting capital expenditure from operating cash.

if r.fcf:
    print(f"FCF: {r.fcf/1e12:,.1f}T KRW")

Persistently negative FCF means the company spends more on investment than it earns from operations.

Operating CF Margin

Operating Cash Flow ÷ Revenue × 100

Comparing this with operating margin reveals the cash conversion quality of earnings.

if r.operatingCfMargin:
    print(f"Operating CF Margin: {r.operatingCfMargin:.1f}%")

Operating CF / Net Income

Operating Cash Flow ÷ Net Income × 100

Above 100% means more cash is coming in than reported profit. Capital-intensive companies normally show 200%+ (due to depreciation).

if r.operatingCfToNetIncome:
    print(f"Operating CF / Net Income: {r.operatingCfToNetIncome:.1f}%")

CAPEX Ratio

|CAPEX| ÷ Revenue × 100

Capital expenditure as a proportion of revenue. Equipment-heavy industries like semiconductors typically show 20%+.

if r.capexRatio:
    print(f"CAPEX Ratio: {r.capexRatio:.1f}%")

Dividend Payout Ratio

|Dividends Paid| ÷ Net Income × 100

What percentage of net income is distributed as dividends.

if r.dividendPayoutRatio:
    print(f"Dividend Payout Ratio: {r.dividendPayoutRatio:.1f}%")

Growth Metrics (6)

if r.revenueGrowth3Y:
    print(f"Revenue 3Y CAGR: {r.revenueGrowth3Y:.1f}%")

In time-series mode (calcRatioSeries), YoY growth rates are also available:

• revenueGrowth: Revenue YoY growth
• operatingProfitGrowth: Operating income YoY growth
• netProfitGrowth: Net income YoY growth
• assetGrowth: Total assets YoY growth
• equityGrowthRate: Equity YoY growth

Raw Data

Raw values used in ratio calculations are also provided:

if r.revenueTTM:
    print(f"TTM Revenue:          {r.revenueTTM/1e12:,.1f}T KRW")
if r.operatingIncomeTTM:
    print(f"TTM Operating Income: {r.operatingIncomeTTM/1e12:,.1f}T KRW")
if r.netIncomeTTM:
    print(f"TTM Net Income:       {r.netIncomeTTM/1e12:,.1f}T KRW")
if r.totalAssets:
    print(f"Total Assets:         {r.totalAssets/1e12:,.1f}T KRW")
if r.totalEquity:
    print(f"Total Equity:         {r.totalEquity/1e12:,.1f}T KRW")

Time-Series Mode — Trend Analysis

Single-period ratios can’t reveal direction. Year-over-year trends show “improving or deteriorating.”

import dartlab

c = dartlab.Company("005930")
rs = c.finance.ratioSeries  # (series_dict, years) tuple

if rs:
    series, years = rs
    ratio_data = series.get("RATIO", {})
    roe_vals = ratio_data.get("roe", [])
    margin_vals = ratio_data.get("operatingMargin", [])

    print(f"Years: {years}")
    print()
    for year, roe, margin in zip(years, roe_vals, margin_vals):
        roe_str = f"{roe:.1f}" if roe is not None else "-"
        margin_str = f"{margin:.1f}" if margin is not None else "-"
        print(f"  {year}: ROE {roe_str:>6}%  OpMargin {margin_str:>6}%")

All 29 ratios available in time-series mode:

Time-series results also include raw value lists: revenue, operatingProfit, netProfit, totalAssets, totalEquity, operatingCashflow

At a Glance

Pattern for printing all financial ratios at once:

c = dartlab.Company("005930")
r = c.ratios

if r:
    def p(label, val, unit="%", fmt=".1f"):
        if val is not None:
            print(f"  {label:20s} {val:{fmt}}{unit}")
        else:
            print(f"  {label:20s} -")

    print(f"=== {c.corpName} Financial Ratios ===")
    print()
    print("[ Profitability ]")
    p("ROE", r.roe)
    p("ROA", r.roa)
    p("Operating Margin", r.operatingMargin)
    p("Net Margin", r.netMargin)
    p("Gross Margin", r.grossMargin)
    p("EBITDA Margin", r.ebitdaMargin)
    p("COGS Ratio", r.costOfSalesRatio)
    p("SG&A Ratio", r.sgaRatio)
    print()
    print("[ Stability ]")
    p("Debt Ratio", r.debtRatio)
    p("Current Ratio", r.currentRatio)
    p("Quick Ratio", r.quickRatio)
    p("Equity Ratio", r.equityRatio)
    p("Interest Coverage", r.interestCoverage, "x")
    p("Net Debt Ratio", r.netDebtRatio)
    p("Non-Current Ratio", r.noncurrentRatio)
    print()
    print("[ Efficiency ]")
    p("Asset Turnover", r.totalAssetTurnover, "x", ".2f")
    p("Inventory Turnover", r.inventoryTurnover, "x", ".1f")
    p("Receivables Turnover", r.receivablesTurnover, "x", ".1f")
    p("Payables Turnover", r.payablesTurnover, "x", ".1f")
    print()
    print("[ Cash Flow ]")
    if r.fcf:
        p("FCF", r.fcf / 1e12, "T KRW", ",.1f")
    p("Op CF Margin", r.operatingCfMargin)
    p("Op CF / Net Income", r.operatingCfToNetIncome)
    p("CAPEX Ratio", r.capexRatio)
    p("Dividend Payout", r.dividendPayoutRatio)
    print()
    print("[ Growth ]")
    p("Revenue 3Y CAGR", r.revenueGrowth3Y)

Comparing Ratios Across Companies

import polars as pl

codes = ["005930", "000660", "035420", "035720", "051910"]
rows = []

for code in codes:
    c = dartlab.Company(code)
    r = c.ratios
    if r is None:
        continue
    rows.append({
        "Company": c.corpName,
        "ROE(%)": round(r.roe, 1) if r.roe else None,
        "OpMargin(%)": round(r.operatingMargin, 1) if r.operatingMargin else None,
        "DebtRatio(%)": round(r.debtRatio, 1) if r.debtRatio else None,
        "CurrentRatio(%)": round(r.currentRatio, 1) if r.currentRatio else None,
        "FCF(T)": round(r.fcf / 1e12, 1) if r.fcf else None,
        "AssetTurnover": round(r.totalAssetTurnover, 2) if r.totalAssetTurnover else None,
    })

df = pl.DataFrame(rows)
print(df)

Same code structure — just change the codes list to compare any companies. 5, 50, or 500, same code.

Formula Reference

Profitability

EBITDA D&A estimation: Tangible Assets × 5% + Intangible Assets × 10% (approximation due to difficulty extracting depreciation from cash flow statements)

Stability

Efficiency

Cash Flow

Growth

Valuation (requires market cap)

Valuation ratios require passing market cap: calcRatios(series, marketCap=market_cap)

Composite Indicators (Distress & Quality)

Beyond traditional ratios, DartLab computes academic-grade composite indicators for distress prediction and earnings quality assessment.

Distress Prediction Models

r = c.ratios
if r and r.ohlsonProbability is not None:
    print(f"O-Score P(bankruptcy): {r.ohlsonProbability:.1f}%")
if r and r.altmanZppScore is not None:
    print(f"Z''-Score: {r.altmanZppScore:.2f}")

Earnings Quality Models

These composite indicators feed into the distress prediction scorecard available via Company.insights.distress. See Insight Grades for details.

Account Mappings (snakeId) Used

Caveats

Industry Comparisons

Financial ratios have no absolute benchmarks. Comparing semiconductor and bank debt ratios is meaningless. Compare within the same industry. → Use sector classification in 8. Cross-Company Comparison

Financial Companies

Banks, insurance, and securities firms have different financial structures, so debt ratio, current ratio, etc. have different meanings. A bank’s 1000% debt ratio is normal (deposits are liabilities). Financial companies may not have revenue, current assets, or inventory accounts at all.

Temporary Distortions

Quarters with large one-time gains/losses can distort TTM ratios. For example, if a quarter with a factory sale gain is included in TTM, ROE will appear abnormally high.

Outlier Filtering

Extreme values are automatically filtered:

• ROE: None if exceeds ±500%
• ROA: None if exceeds ±200%
• Debt Ratio: None if exceeds 5000%
• Current Ratio: None if exceeds 10000%

EBITDA Estimation

Since extracting depreciation as a separate account from DART data is difficult, it’s estimated as tangible assets × 5% + intangible assets × 10%. EBITDA margin may be inaccurate for companies where actual depreciation significantly differs from this range (e.g., airlines).

Next Steps

• 5. Report Data — Dividends, employees, shareholders, audit, etc.
• 6. Disclosure Text — Business description, MD&A