A statement is a sentence whose purpose is primarily to convey information. It usually has two criteria:
1) The clause contains a subject.
2) The subject precedes the verb.
These sentences are said to have a declarative structure.
In conversation, the subject is often omitted from a declarative sentence:
Looks like snow. Told you so. Beg pardon.
There are a very few cases where the subject follows a verb. This happens when the clause begins with words like 'hardly' and 'scarcely', which express a negative meaning.
Hardly had he left, when the heavens opened.