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joellewis avatar

Return Calculations

joellewis/finance_skills
449 installs164 stars
Summary

When you need to explain why a fund's 8% time-weighted return translates to a negative money-weighted return for an investor who deposited right before a drawdown, this is the skill to load. It covers the full spectrum from simple holding period returns through CAGR, TWR, MWR/IRR, and the math behind geometric versus arithmetic means. The worked examples are solid, showing exactly how cash flow timing creates divergence between what the manager earned and what the investor experienced. It's Layer 0 math, so expect formulas and precision rather than high-level commentary. Use it when someone asks about portfolio performance, linking sub-period returns, or why their actual return feels different from what their advisor reported.

Install to Claude Code

npx -y skills add joellewis/finance_skills --skill return-calculations --agent claude-code

Installs into .claude/skills of the current project.

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Monitor with ease. Code with confidence.
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Connect your Claude agent to live crypto prices and trading routes via 1inch
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CodeRabbit
CodeRabbit
AI writes the code. CodeRabbit catches the slop.
Try For Free →
Lid closed, agents working
Lid closed, agents working
Keeps your Mac awake while Claude Code, Codex or Cursor works. Lets it sleep when they are done.
Try free for 7 days →
Block distraction from your iPhone for freeBlock distraction from your iPhone for free
Block distraction from your iPhone for free
Block distracting apps from your iPhone permanently without a 3rd party app. Free and open source.
Block now (100% free) →
Granola, the best AI meeting recorder
Granola, the best AI meeting recorder
Notes, actions and memory. Without a meeting bot. First month 100% off.
Download for free →
belt - the only tool your agent needs
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belt cli automatically finds the best tools and skills for your agent. image, video, music, tts...
one prompt install →
Open Steps
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Free an open-source skills that make AI coding agents easier to understand, verify, and control.
Download for free →
AppSignal
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Monitor with ease. Code with confidence.
Start Free Trial →
Agent, connect blockchain
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Connect your Claude agent to live crypto prices and trading routes via 1inch
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Files
SKILL.md

Select a file.

Featured
CodeRabbit
CodeRabbit
AI writes the code. CodeRabbit catches the slop.
Try For Free →
Lid closed, agents working
Lid closed, agents working
Keeps your Mac awake while Claude Code, Codex or Cursor works. Lets it sleep when they are done.
Try free for 7 days →
Block distraction from your iPhone for freeBlock distraction from your iPhone for free
Block distraction from your iPhone for free
Block distracting apps from your iPhone permanently without a 3rd party app. Free and open source.
Block now (100% free) →
Granola, the best AI meeting recorder
Granola, the best AI meeting recorder
Notes, actions and memory. Without a meeting bot. First month 100% off.
Download for free →
belt - the only tool your agent needs
belt - the only tool your agent needs
belt cli automatically finds the best tools and skills for your agent. image, video, music, tts...
one prompt install →
Open Steps
Open Steps
Free an open-source skills that make AI coding agents easier to understand, verify, and control.
Download for free →
AppSignal
AppSignal
Monitor with ease. Code with confidence.
Start Free Trial →
Agent, connect blockchain
Agent, connect blockchain
Connect your Claude agent to live crypto prices and trading routes via 1inch
Get the MCP →
Categories
DebuggingFinance & Trading
First SeenJun 3, 2026
View on GitHub

More from joellewis/finance_skills

All 84 skills →
  • Anti Money Laundering447
  • Fund Vehicles447
  • Lending447
  • Know Your Customer446
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  • Next Best Action445
  • Tax Efficiency444
  • Digital Assets443
  • Tax Loss Harvesting443
  • Fixed Income Corporate442
  • Forward Risk439
  • Investment Suitability439
  • Regulatory Reporting439
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  • Exchange Connectivity438
  • Operational Risk437
  • Order Management Advisor436
  • Savings Goals436
  • Books And Records435
  • Advice Standards434
  • Fixed Income Sovereign434
  • Margin Operations434

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