A visitor is a person who is coming to the UK, usually for up to six months, for a temporary purpose, for example as a tourist, to visit friends or family or to carry out a business activity.
Visit visas are not granted for the purpose of living in the UK or making the UK their home through frequent and successive visits, therefore the information requested is not available
Individuals in the UK as visitors may extend their visit whilst in the UK, as long as the total stay does not exceed 6 months.
Applications to switch from visit to spouse or child settlement visa applications need to be made from overseas. Information on the number of in country extensions for main applicants previously in the visitor category is published in the quarterly Immigration Statistics, extensions table expc_01, latest edition at https://www.gov.uk/government/publications/immigration-statistics-year-ending-september-2018/list-of-tables