Required Columns
- Symbol (e.g., AAPL, SHEL.L, SIE.DE)
- Name (e.g., Apple Inc.)
- Type (Stock, ETF, Cryptocurrency)
- Exchange (Code, e.g., NASDAQ, LSE)
- Currency (USD, EUR, GBP)
Symbol Tip: Use Yahoo Finance tickers. US: AAPL; London: SHEL.L; Frankfurt: SIE.DE; Paris: AIR.PA; Crypto: BTC-USD.