historical-market-cap

name	historical-market-cap
description	Retrieve historical market capitalization data for any stock using the Octagon Claude plugin. Use when tracking market cap changes over time, analyzing valuation trends, identifying peak and trough valuations, and comparing historical size classifications.

Historical Market Cap

Retrieve historical market capitalization data over a specified date range using the Octagon Claude plugin.

Prerequisites

Ensure the Octagon Claude plugin is installed and configured in Claude Code before invoking this skill.

Workflow

1. Identify Parameters

Determine your query parameters:

• Ticker: Stock symbol (e.g., AAPL, MSFT)
• Start Date: Beginning of date range
• End Date: End of date range
• Limit (optional): Maximum records to return

2. Execute Query via the Octagon Claude plugin

Use the octagon-agent tool with a natural language prompt:

Retrieve historical market capitalization data for <TICKER> from <START_DATE> to <END_DATE>, limited to <LIMIT> records.

MCP Call Format:

{
  "server": "octagon-claude-plugin",
  "toolName": "octagon-agent",
  "arguments": {
    "prompt": "Retrieve historical market capitalization data for AAPL from 2025-01-01 to 2025-04-30, limited to 1000 records."
  }
}

3. Expected Output

The agent returns daily market cap values:

Date	Market Cap (USD)
2025-04-30	$3.17 trillion
2025-02-25	$3.70 trillion (High)
2025-04-08	$2.57 trillion (Low)
...	...

Summary Statistics:

• Highest: $3.70 trillion on 2025-02-25
• Lowest: $2.57 trillion on 2025-04-08
• Most Recent: $3.17 trillion on 2025-04-30

Data Sources: octagon-stock-data-agent

4. Interpret Results

See references/interpreting-results.md for guidance on:

• Analyzing market cap trends
• Calculating growth rates
• Identifying peaks and troughs
• Understanding volatility

Example Queries

Standard Date Range:

Retrieve historical market capitalization data for AAPL from 2025-01-01 to 2025-04-30, limited to 1000 records.

Full Year:

Get historical market cap for MSFT for the entire year 2024.

Quarterly Analysis:

Show TSLA's market cap history for Q1 2025.

Multi-Year Trend:

Retrieve market cap history for NVDA from 2020 to 2025.

Peak Analysis:

When did AAPL reach its highest market cap in 2024?

Understanding Market Cap History

What the Data Shows

Metric	Description
Daily Market Cap	End-of-day value
Date Series	Trading days only
Calculation	Price × Shares Outstanding
Adjustments	Split-adjusted shares

Key Statistics

Statistic	Purpose
Maximum	Peak valuation
Minimum	Trough valuation
Average	Typical valuation
Range	Volatility indicator

Trend Analysis

Calculating Changes

Metric	Formula
Absolute Change	End Cap - Start Cap
Percentage Change	(End - Start) / Start × 100%
CAGR	(End/Start)^(1/years) - 1

Example Calculation

From the AAPL data:

• High: $3.70T (Feb 25)
• Low: $2.57T (Apr 8)
• Range: $1.13T
• Peak-to-Trough: -30.5%

Trend Patterns

Pattern	Characteristics
Uptrend	Higher highs, higher lows
Downtrend	Lower highs, lower lows
Consolidation	Range-bound
V-Recovery	Sharp decline, sharp recovery
Rounded Top	Gradual peak formation

Period Analysis

Daily Analysis

Use Case	Focus
Trading	Short-term moves
Volatility	Day-to-day changes
Events	Catalyst impact

Weekly/Monthly Analysis

Use Case	Focus
Trends	Direction over time
Comparisons	Period-over-period
Smoothing	Reduce noise

Annual Analysis

Use Case	Focus
Growth	Long-term trajectory
Milestones	Major achievements
CAGR	Compound growth

Volatility Assessment

Measuring Volatility

Metric	Calculation
Range	High - Low
Range %	(High - Low) / Average
Daily Moves	Average daily change
Standard Deviation	Price dispersion

Volatility Interpretation

Range %	Volatility
<20%	Low
20-40%	Moderate
40-60%	High
>60%	Very High

Example

From AAPL data:

• High: $3.70T
• Low: $2.57T
• Range: $1.13T
• Range %: ~35%
• Interpretation: Moderate-high volatility

Peak and Trough Analysis

Identifying Peaks

Signal	Description
All-time High	Highest ever
Period High	Highest in range
Local Peak	Temporary high

Identifying Troughs

Signal	Description
All-time Low	Lowest ever
Period Low	Lowest in range
Local Trough	Temporary low

Peak-to-Trough Metrics

Metric	Purpose
Drawdown %	Decline from peak
Recovery Time	Days to recover
Drawdown Duration	Peak to trough time

Size Classification Over Time

Tracking Category Changes

If Market Cap...	Classification
>$200B	Mega-cap
$10B-$200B	Large-cap
$2B-$10B	Mid-cap
$300M-$2B	Small-cap

Milestone Analysis

Milestone	Significance
First $1T	Historic achievement
Crossed $2T	Elite status
Crossed $3T	World's most valuable

Comparative Analysis

Same Company Over Time

Comparison	Purpose
YoY	Year-over-year growth
QoQ	Quarterly momentum
MoM	Monthly trends

Multiple Companies

Comparison	Purpose
Relative Size	Market position
Relative Growth	Performance comparison
Correlation	Movement similarity

Common Use Cases

Trend Analysis

How has AAPL's market cap changed over the past year?

Peak Finding

When did TSLA reach its highest market cap?

Drawdown Analysis

What was NVDA's biggest decline from peak in 2024?

Milestone Tracking

When did MSFT first cross $3 trillion market cap?

Comparison

Compare the market cap growth of AAPL and MSFT over 5 years.

Analysis Tips

1. Use appropriate timeframes: Match analysis to investment horizon.

2. Identify catalysts: Major moves often have drivers.

3. Consider splits: Ensure data is split-adjusted.

4. Watch for milestones: Round numbers are psychologically important.

5. Calculate drawdowns: Understand downside risk.

6. Compare to benchmarks: Market cap vs. index performance.

Integration with Other Skills

Skill	Combined Use
company-market-cap	Current vs. historical
stock-performance	Price driving cap changes
income-statement	Earnings supporting cap
financial-metrics-analysis	Valuation evolution