For statistical purposes in the United Kingdom, a household is defined as "one person or a group of people who have the accommodation as their only or main residence and for a group, either share at least one meal a day or share the living accommodation, that is, a living room or sitting room". The introduction of legislation to control houses of multiple occupation in the UK Housing Act (2004) required a tighter definition of a single household. People can be considered a household if they are related: full- or half-blood, foster, step-parent/child, in-laws (and equivalent for unmarried couples), a married couple or unmarried but "living as ..." (same- or different-sex couples).