Book value is a term used in accounting and finance to refer to the total value of a company's assets, minus the total value of its liabilities. In other words, it represents the value of the company if all of its assets were sold and all of its debts were paid off.

The book value is also sometimes referred to as the "net asset value" or the "carrying value" of the company.

Example:

Berkshire Hathaway's book value for the year 2021:

• Total assets: $894.6 billion
• Total liabilities: $453.1 billion

To calculate the book value, you would subtract the total liabilities from the total assets:

Book Value = Total Assets - Total Liabilities 

Book Value = $894.6 billion - $453.1 billion 

Book Value = $441.5 billion

In this example, Berkshire Hathaway has a book value of $441.5 billion for the year 2021. This means that if the company were to sell all of its assets and pay off all of its liabilities, it would have $441.5 billion left over.

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