Stop the Blended Average Trap

The Blended Average Trap — Why One Number Lies

It is Tuesday morning. You open your broker app and check your portfolio. TITAN is showing at ₹3,100. You bought it at a blended average of ₹3,000. You are up +3.33%. Everything looks fine. You move on.

But here is what that blended average is hiding:

The Zerodha position is down -7.5%. It has crossed your -5% stop-loss. It should have been exited. But the Groww position — bought lower after a re-entry — is doing beautifully at +10.7%. The blended average merges these two completely different investment decisions into one number: +3.33%. And +3.33% does not tell you to do anything.

This is the Blended Average Trap. It is not a failure of arithmetic. It is a failure of design. Any tracker that blends your cost across entries, brokers, or purchase dates is hiding information you need to make decisions.

The same trap applies when you sell a position after a stop-loss breach and later re-enter the same stock from a different broker at a new cost basis. A tracker that blends your historical trades will show you a fictitious average. Finmagine shows you exactly what you paid, when, from which broker — and compares it against the live price. No averaging. No hiding.

What Is Finmagine Portfolio Manager?

Finmagine Portfolio Manager is a Chrome extension that tracks your Indian and global investments across up to 9 brokers simultaneously, fetches live prices and fundamentals from Screener.in and ChartInk, computes annualised XIRR per holding, shows index beat vs Nifty 50/500, and provides on-demand charts — all locally, with no server required for core functionality.

Four Asset Classes, One Unified View

Most Indian investors hold more than just NSE stocks today. Mutual funds, US ETFs through INDMoney or Vested, direct US stocks through Fidelity or IBKR — all of these need to be tracked together to get a true picture of your portfolio. Finmagine Portfolio Manager handles all four in one place.

Indian Equities (IN_EQ)

The core asset class. Full charges breakdown at trade entry (STT, exchange fee, stamp duty, SEBI turnover fee, brokerage, GST). All 9 broker columns visible. Every column from PEG to Index Beat to Signals is available. The full Watchlist tab with 23 fundamental columns is available here.

Global Equities (GL_EQ) USD

US stocks held through platforms like INDMoney, Fidelity, Schwab, or IBKR. Prices in USD, converted to ₹ at the FX rate in your settings (default ₹84/USD). Charges: ~0.03% SEC fee on sell only. Full Watchlist tab is available for GL_EQ (stockanalysis.com powers fundamentals for US stocks).

Indian Mutual Funds (IN_MF) NAV

Add any AMFI-registered direct or regular scheme by searching the fund name — the scheme code is resolved automatically. NAV fetched from api.mfapi.in. Zero charges (direct plans). Fractional units supported. Columns: Fund | NAV ₹ | P&L% | XIRR | N50 | N500 | Invested ₹ | Value ₹ | Units | Platform | Weight%.

Global Funds & ETFs (GL_MF) USD

ETFs (VOO, SPY, QQQ) and US mutual funds (FBGRX, FDIVX from Fidelity) tracked exactly like GL_EQ via Yahoo Finance. Zero charges. Fractional units supported. If you hold Vanguard ETFs at Vanguard.com, or Fidelity mutual funds at Fidelity.com, this is the asset class for them.

Per-Broker Tracking — The Core Innovation

Every trade you enter has three key identifiers: the stock symbol, the broker, and the date. Finmagine Portfolio Manager uses all three. Specifically, it treats each stock + broker combination as a distinct position. If you hold TITAN at Zerodha and TITAN at Groww, those are two separate rows in your Holdings table — each with its own buy price, P&L%, stop-loss status, and XIRR.

The 9 Broker Columns

The Holdings table has a broker column for each of the 9 supported Indian brokers. Each column shows the P&L% for that specific stock at that specific broker. Cells are left empty if you don't hold the stock there.

The red badge on TITAN's Zerodha column tells you exactly what the blended +3.3% was hiding: that position hit your stop-loss three percentage points ago.

The Stop-Loss Badge System

The extension continuously monitors every broker cell. When a position's P&L% falls below -5%, the cell turns red and shows a ⚠ warning icon. When it is within 1% of the threshold (between -4% and -5%), the cell turns amber. The Chrome extension icon badge also shows the count of active stop-loss breaches across your entire portfolio.

One Stock, Multiple Entries, Multiple Chapters

Consider this realistic scenario: You bought ZOMATO at ₹230 in Zerodha in December. It fell to ₹200 and you exited (stop-loss triggered). In January, the setup looked good again, so you re-entered from Groww at ₹185. The price is now ₹215.

• The Zerodha entry: CLOSED (you sold). This trade is recorded and contributes to your realized P&L history.
• The Groww entry: ACTIVE at +16.2%. This is a fresh position with a clean cost basis.
• If you had a blended tracker, it would average ₹230 and ₹185 to show ₹207.50, up +3.6%. Neither story is told accurately.

The Holdings Table — What Every Column Tells You

The Indian Equities Holdings table is the densest and most information-rich view in the extension. Here is a reference for every column:

Every column is sortable. Click a column header once to sort descending, again to sort ascending. Sorting by Score and then by N50 is a powerful two-pass filter for stocks that are both technically strong and have genuinely beaten the index since your entry date.

The Stats Strip

Above the Holdings table sits a compact stats strip that answers the five most common quick questions about your portfolio:

• Today Δ% — Your portfolio's aggregate day change based on all holdings' prev-close vs LTP
• XIRR p.a. — Portfolio-level annualised return across all trades
• Since — Date of your earliest trade + total days held
• Nifty 50 — Current Nifty 50 index level
• Movers — How many stocks in your portfolio are up ≥5% or down ≤-5% today

Seven Tabs at a Glance

Beyond Holdings, six more tabs each answer a specific portfolio management question:

The Watchlist Tab

The Watchlist tab is a 23-column fundamental comparison table. All of your Holdings are automatically included (tagged with a HOLD badge). You can manually add any additional stock you are researching. Columns include:

LTP | Score | Signals | PEG | P/E | P/B | P/S | EV/EBITDA | ROCE | ROE | D/E | Current Ratio | Interest Coverage | OPM% | NPM% | Sales Growth% | EPS Growth% | FCF | Pledging% | Promoter% | FII%

Each metric is color-coded (green/yellow/orange/red) based on sector-appropriate thresholds from Screener.in. Trend badges (↑/↓/→) appear on OPM%, NPM%, Sales%, and EPS% to show direction over the past year. Everything is sortable, cached for 90 days, and loaded lazily on first tab click.

XIRR & Index Beat — Are You Really Beating the Market?

P&L% tells you how much you made. XIRR tells you how fast you made it. A +30% return over 5 years is very different from a +30% return over 18 months. XIRR normalises all of this into an annualised percentage, making every holding comparable regardless of when you bought it.

XIRR Per Holding

For each stock, the extension takes every buy trade as a cash outflow (negative) on its purchase date, and the current market value as a hypothetical sell (positive) on today's date. It then solves for the discount rate that makes the net present value of all cash flows equal to zero — this is the XIRR.

Index Beat (N50 / N500)

The N50 and N500 columns answer a question P&L% cannot: did I beat the benchmark from my specific entry date? For each holding, the extension looks up the Nifty 50 and Nifty 500 index level on the exact date of your earliest trade in that stock, and computes what those indices returned from that date to today.

Example: You bought IREDA at ₹180 on January 15, 2024. LTP today is ₹210. Your P&L% is +16.7%. But Nifty 50 returned +11.2% and Nifty 500 returned +13.8% from that same date. So your Index Beat is +16.7% − 13.8% = +2.9% over N500. That is real alpha — not impressive alpha, but real.

Index data is fetched once from Yahoo Finance and cached permanently per date. Once you have the Nifty level for a specific date, you never fetch it again. The Index Beat calculation is instant from then on.

Portfolio XIRR (All ACs, Unified ₹)

The stats strip shows a single Portfolio XIRR computed across all trades in all four asset classes. USD trades are converted to ₹ at the FX rate in your settings. This gives you one honest answer to the hardest portfolio question: what is my actual annualised return, accounting for the timing of every rupee I deployed?

Getting Started in 3 Steps

Once Finmagine Portfolio Manager is available on the Chrome Web Store, getting started takes about 5 minutes from install to your first live portfolio view.

Or: Import Your Existing Trades via CSV

If you already have your trade history in a broker export, use the Import feature. Supported formats:

• Generic CSV — Universal format: symbol, broker, type, date, price, qty, asset_class columns
• Zerodha Tradebook — Direct export from Zerodha Console
• Groww Tradebook — Direct export from Groww Portfolio
• Angel One — Trades export from Angel One SmartAPI
• Upstox Holdings — Holdings export from Upstox

Settings Worth Configuring First

Before your first price refresh, visit the Settings tab and set:

• USD/INR Rate — Current exchange rate (default ₹84). Affects all GL_EQ and GL_MF valuations.
• Stop-Loss Threshold — Your per-broker exit trigger. Default -5%.
• Consider Threshold — Minimum invested to consider a position "alloted". Default ₹3,00,000.
• Invest Amount — Sticky value for the Buy Qty calculator column. Enter how much you plan to invest per trade.

What’s Next in This Series

This is article 1 of 6 in the Finmagine Portfolio Manager series. Each article goes deep on one aspect of the extension — from the stop-loss philosophy to charts to multi-asset tracking.

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