Because of dramatic levels of economic volatility and massive changes in welfare policies, scholars in this decade worried anew about whether our official poverty measure, adopted in the 1960s, is adequate. Poverty's causes continued to be debated, with demographic factors often pitted against policy and maternal employment changes. Some scholars focused on events that trigger spirals into poverty or poverty exits. The literature on consequences of poverty featured new techniques for identifying underlying processes and mechanisms. Researchers also explored "neighborhood effects" and focused on poverty deconcentration efforts. Finally, scholars produced a voluminous literature on the efforts to reform welfare and their subsequent effects.