“…In Eastern Europe and post-Soviet Asia, the limitations of the extant literature on flat tax are compounded by the absence of reliable data regarding successive pre-and post-socialist tax schedules and tax breaks (for partial exceptions, Erd} os, 1992;Tanzi, 1993;Tanzi and Tsibouris, 2000). Beyond the absence of scholarly knowledge on issues of personal income taxation from a longer historical perspective, including tax breaks for social purposes (Adema et al, 2011) that together constitute 'fiscal welfare' (Titmuss, 1987: 48), one analytical implication is that the varieties of post-communist welfare regimes (Fenger, 2007;Kuitto, 2016), which have often made use of welfare effort indicators, have been incomplete (for a similar problem in OECD countries, see Morel et al, 2018;Sinfield, 2012).…”