Modified from Table 3 in Newhall, CG, and S Self, 1982, The volcanic explosivity index (VEI): An estimate of explosive magnitude for historical volcanism: Journal of Geophysical Research87, 1231-1238.  Additional eruptions added from tree ring data reported in Table 2 of Briffa, KR, PD Jones, FH Schweingruber & TJ Osborn, 1998, Influence of volcanic eruptions on Northern hemisphere summer temperature over the past 600 years: Nature 393, 450-455.  Note that other large eruptions occurred during the last 600 years, according to tree ring and ice core data, but are not indicated here because the source volcano is unknown (e.g. 1809).