What is the purpose of Form 4684?

Form 4684 is specifically designed to declare casualty and theft losses on tax returns. This form allows taxpayers to report losses resulting from various incidents, such as natural disasters, theft, or other situations that lead to the deterioration or loss of property.

When filling out Form 4684, taxpayers must provide specific details regarding the nature of their losses, the types of property affected, and the amount of the losses. This information is essential because it helps the IRS assess the taxpayer's situation and determine appropriate tax deductions related to those losses.

The other options relate to different aspects of tax reporting. For instance, reporting additional income from charitable contributions pertains to different forms and scenarios. Calculating capital gains from property sales involves other forms like Schedule D, while documenting personal investments doesn't involve Form 4684. Therefore, the primary and correct purpose of Form 4684 is indeed to declare casualty and theft losses on tax returns.