NEWMARKET, UK--Improved trade punctuated by a steady stream of notable results for the progeny of Dragon Symbol would be a neat summation of Tuesday's opening session of the December Foal Sale at Tattersalls, with Whitsbury Manor Stud's first-crop sire alone accounting for nearly 25% of the 1,684,200gns that changed hands on the day. That total turnover represented a 23% increase compared to 12 months ago, while the average and the median also painted a much prettier picture as opposed to what was a sluggish start to last year's December Foal...