TY JOUR TI Statistical Study of Demographic Indicators of Tula region KW mortality KW fertility KW natural growth KW natural decline KW demographic load KW depopulation KW demographic aging KW demographic echo KW working age KW migration KW quality of life JO Scientific Research and Development. Economics AU Avdeeva, A.E. AU Kalyanov, A.Y. PY 2019 IS 7 PB INFRA-M Academic Publishing LLC.