C# models to track investment portfolios
Instrument (entity, aggregate root) represents a financial instrument by its symbol, name, and current price.
Lot (entity, aggregate root) represents a lot - record of financial trade involving Instrument.
Holding (entity) represents a portfolio subset, targeting a single instrument, by aggregating lots buying that instrument.
Portfolio (entity, aggregate root) represents a single portfolio, aggregating holdings that the portfolio consists of.
PortfolioGroup (entity, aggregate root) represents a set of portfolios, for expressing a bigger picture.