During Phases I and II, allowances for emissions have typically been given free to firms, which has resulted in them getting windfall profits. Ellerman and Buchner (2008) suggested that during its first two years in operation, the EU ETS turned an expected increase in emissions of 1%-2% per year into a small absolute decline. Grubb "et al." (2009) suggested that a reasonable estimate for the emissions cut achieved during its first two years of operation was 50-100 MtCO2 per year, or 2.5%-5%.