is the price of the company's common stock as of the close of the previous trading day as reported by the security's primary exchange.
The market price at any given time.
The amount of money a security most recently traded for.
As these G-secs are traded in the secondary market the price of these G-secs fluctuates according to the demand/supply in the market for that security. The current price is the prevailing price in the secondary market.
The current price listed in your portfolio is the most recent price for that security available.