Is unrealized gain part of asset?
Stocks, as an asset, represent the sum of the current market value of all of your holdings. If your portfolio is showing unrealized gains and losses, then that net amount is inherently reflected in the current market value of your holdings.  That's not to say cost basis is not important. Any closed trades, realized gains or losses, will of course have an impact on your taxable income. So, it couldn't hurt to keep track of your cost basis from a tax standpoint, but understand that the term "asset" refers to the current market values and does not consider base amounts. Taxes do. Perhaps consider making separate cells for cost basis, but also bear in mind that most if not all of the major online discount brokers will provide transferring of cost basis information electronically to the major online tax service providers.