Internal (within the UK) migration has been negative; that is the numbers of people moving out of London has been greater than the number of UK residents moving in. This balance has got smaller over time.
International
International net migration has always been positive during the time period shown, so there have always been more foreign born people moving into London than out of it
Natural change/increase
Natural Change has been positive, so births have been above deaths and this has boosted the population size
