Chart of the years 1842-1851 showing how much grain was imported & exported to/from Ireland. In 1842-5 it runs 2-3 million quarters per year; a quarter is a little over 1/4 ton, so 0.5 to 0.75 million tons per year of grain per year leading up to the 1847 famine. In 1847 exports slowed to 1M quarters, or 0.25M tons of grain exported from Ireland during famine, and quickly rebounding to close to 2M quarters or 0.5M tons of grain per year from 1848 onward. Source: https://en.wikipedia.org/wiki/Great_Famine_(Ireland)#Food_exports
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