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📖 Book Value

⬅️ Back to Performance Metrics Overview

💡 What is Book Value?

Book Value represents the historical accounting cost of your portfolio — how much capital you deployed at cost, plus cash reserves. It does not fluctuate with market prices.

🧮 Formula

\[ \boxed{\mathrm{Book}(t) = \mathrm{OCB}(t) + \mathrm{Cash}(t) + \mathrm{InTransitBook}(t)} \]

Where Open Cost Basis:

\[ \mathrm{OCB}(t) = \sum_{\substack{(a,b) \in S \\ q > 0}} q(a,b,t) \cdot w(a,b,t) \cdot \mathrm{fx}(\mathrm{ccy}_w, C^*, t) \]

🔗 See Portfolio Engine — §3 Position State for full derivation.

⚖️ Unrealized Gain/Loss

\[ \mathrm{Unrealized}(t) = \mathrm{NAV}(t) - \mathrm{Book}(t) \]

📝 Example

Component Amount
Open Cost Basis €27,000
Cash €600
In-Transit Book €0
\[ \mathrm{Book} = 27\,000 + 600 = 27\,600 \text{ EUR} \]

With NAV = €33,000:

\[ \mathrm{Unrealized} = 33\,000 - 27\,600 = +5\,400 \text{ EUR} \]
  • 📊 WAC — unit cost method for OCB
  • 💼 NAV — market-value counterpart
  • 📈 Period PnL — realized + unrealized combined