U3 and U6 Unemployment during the Great Depression

A frequent meme propounded in the economic blogosphere is that U6 unemployment, running near 17% now, is a truer measure (and there are good reasons to believe it is), so that means we have unemployment already approaching Great Depression levels of 25%. Left out of the comparison is the fact that U3 and U6 measurements didn't exist during the 1930s. So, is the 25% unemployment peak for the Great Depression a fair comparison to U6 unemployment today?

N. Andrews compared historical versions of unemployment statistics with the modern U3 and U6 versions, published as "Historical Unemployment in Relationship to Today" , has an answer. He writes: