Thanks for your reply. Let me explain.

You assumed the current stock price x no. of stock issued in a single exchange market = total present market value of the corporation. This is common mistake that a student would made in an examination.

Say, It's not like you can buy the entire Nokia if you've 24.5 billion on your disposal. The stock price would be hypering up immensely once you acquired more than 5% of the total shares in the NYSE.

There are many other factors taking into consideration. Options issued for one is a major factor that affect the present market value.

Also, you assumed stocks exchanged in NYSE represent everything in Nokia. There might be many major stakeholders of a corp outside of one single exchange market. Therefore, we always rely on financial evaluators to perform valuation of a corp, or buy some expensive financial reports.

I got this figure from a paid european financial report I read weeks ago. I didn't look into detail how they come up with this figure and I believe their valuation would be biased for a Finland company, but I don't own and has not intention to own any Nokia's stock anyway.