Income received from investment assets, such as stocks, bonds, mutual funds and loans, minus related expenses.
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For insurance companies, net investment income represents the amount of income left after operating expenses are subtracted from total investment income.
Net investment income is typically expressed on a per share basis and is calculated pre-tax. To figure the per share net investment income of a company, divide the net investment income by the shares outstanding. This results in the amount available to shareholders in the form of dividends.