I am not a Social Security guru, but I was surprised to receive my annual earnings statement today and find that the estimated benefits for ages 62, 66 and 70 were $30 to $50 per month lower than they were last year and than the SSA's online estimator gave me three months ago. I am nearly 61, and my 2009 earnings were my highest. I thought this was pretty much impossible, and I am not finding any answers on the SSA's site or through Google. Am I missing some obvious explanation?